11:35pm -- A somewhat stunning statement from Rep. Barney Frank (D-MA): "If Coakley had won, I believe we could have worked out a reasonable compromise between the House and Senate health care bills. But Since Brown has won and the GOP now has 41 votes in hte Senate, that approach is no longer appropriate. I am hopeful that some GOP Senators will be willing to discuss a revised version of health care reform because i do not think the country would be well served by the health care status quo. But our respect for Democratic procedures must rule out any effort to pass a health care bill as if the Massachusetts election had not happened. I hope there will be a serious effort to change the senate rule which means that 59 votes are not enough to pass major legislation, but those are the rules by which the health care bill was considered and it would be wrong to change them in the middle of this process." - Mike Memoli

10:56pm -- PA Sen candidate/Rep. Joe Sestak: "The message to Democrats is clear. People have had enough of establishment politics on both sides, such as Senator Specter's party switch after 30 years as a Republican in order to save his job. The people are looking for a new generation of accountable leadership." - Kyle Trygstad

10:42pm -- Brown gives big shout out to Mitt Romney. Some props to McCain as well. - Tom Bevan

10:38pm -- Reax from Harry Reid: “The people of Massachusetts have spoken. We welcome Scott Brown to the Senate and will move to seat him as soon as the proper paperwork has been received. I want thank Senator Paul Kirk for his tremendous service over the last few months. His service to the people of Massachusetts in the place of his friend, Senator Ted Kennedy, was brief but honorable.

“While Senator-elect Brown's victory changes the political math in the Senate, we remain committed to strengthening our economy, creating good paying jobs and ensuring all Americans can access affordable health care. We hope that Scott Brown will join us in these efforts. There is much work to do to address the problems Democrats inherited last year, and we plan to move full speed ahead.

“Regardless of the size of their minority caucus, Senate Republicans have always had an obligation to join us in governing our nation through these difficult times. Today's election doesn't change that; In fact it is now more important than before for Republicans to work with us rather than against us if we are to find common ground that improves Americans' lives.” - Tom Bevan

10:31pm -- Twenty bucks says the GOP replaces its slogan "Drill, Baby, Drill" with "Gas Up the Truck." - Tom Bevan

10:27pm -- Democratic polling firm PPP's 3 takeaways from tonight: 1) This was a repudiation of Barack Obama; 2) Republicans win when they nominate mainstream candidates; 3) Voters hate both parties right now and that's to the GOP's advantage. - Tom Bevan

10:25pm - Interesting to see Mitt Romney gets a speaking slot before Brown tonight. He looks to own Brown win -- Mike Memoli
10:22pm -- Sarah Palin posted a congratulatory note to her Facebook page a few hours ago anticipating a Brown victory: "Congratulations to the new Senator-elect from Massachusetts! Scott Brown's victory proves that the desire for real solutions transcends notions of “blue state” and “red state”. Americans agree that we need to hold our politicians accountable and bring common sense to D.C." - Tom Bevan

10:18pm -- Adding insult to injury, WBZ-TV reports that Scott Brown carried Ted Kennedy's home precinct in Hyannis -- Mike Memoli

10:14pm -- The piling on continues. Gilbert Baker, the Republican challenging Blanche Lincoln in Arkansas, issues a statement saying, "“Congratulations to Scott Brown for his impressive win in Massachusetts. Even President Obama himself couldn't stop the will of the people, painting the bluest of the blue states red. The huge voter turnout is a clear indication that the wave of discontent among voters is at an all time high. Bay State voters, like people across America, are fed up with Obama's big-government agenda and are speaking from the ballot box. I will be a check and balance to the democratic leadership in Washington. Blanche Lincoln should look at this and realize if Democrats can't win in Massachusetts, she can't win in Arkansas.” - Tom Bevan

10:08pm -- Norah O'Donnell reports that just about every Democratic House member she's talked to says they do not have the appetite to pass the Senate bill as is. - Tom Bevan

10:07pm -- A question for Coakley, clearly humbled by tonight's loss: does she run for re-election in November? Will Democrats even let her run unopposed? -- Mike Memoli

10:02pm -- From Robert Gibbs: "This evening the President spoke to both candidates in the hard-fought Massachusetts Senate race. The President congratulated Senator Brown on his victory and a well-run campaign. The President told Senator Brown that he looks forward to working with him on the urgent economic challenges facing Massachusetts families and struggling families across our nation." -- Mike Memoli

10:01pm -- Coakley concession speech: "I will never forget the energy, and the passion, and the soul that we brought to this." Also thanked President Obama, who called her and said, "We can't win them all." - Kyle Trygstad

9:59pm -- More from Rasmussen's election day poll: 52% of Brown voters say health care was the most important issue in determining their vote. 63% of Coakley voters say the same. - Mike Memoli

9:56pm -- Watching Martha Coakley all I can wonder is what Deval Patrick is thinking. Probably something like, "Holy crap. My days are numbered." - Tom Bevan

9:53pm -- The statement from Webb and the earlier comments from Evan Bayh indicate moderate Senate Dems have seen enough. But what about Pelosi? Is she going to continue with the "full speed ahead, business as usual" shtick? It's hard to imagine that we won't see some House Blue Dogs come out with some serious push back after they digest what just happened in Massachusetts. In other words, it's hard to see how the entire health care push doesn't collapse. - Tom Bevan

9:48pm -- And boom goes the dynamite: here's a statement from Sen. Jim Webb: "It would only be fair and prudent that we suspend further votes on health care legislation until Senator-elect Brown is seated." -- Mike Memoli

9:47pm -- Norah O'Donnell of MSNBC reports the Brown campaign says Obama just called to congratulate the new junior Senator from Massachusetts. - Tom Bevan

9:45pm -- Speaking of 2012, Ed Carson says tonight was a big victory for Mitt Romney as well. - Tom Bevan

9:44pm -- From 2012 ranks, Tim Pawlenty: "[Brown's] victory is an inspiration to conservatives across the country to continue our fight for freedom from an overbearing federal government." -- Mike Memoli

9:43pm - From the ranks of other long-shot Republicans, Rick Lazio tells supporters in an e-mail tonight: "I am proud to let you know that the same campaign team that handled Scott Brown's race in Massachusetts is intimately involved with our campaign here in New York." -- Mike Memoli

9:40pm -- EMILY's List: "Every one of us who believes in President Obama's agenda and progressive change got a real wake-up call today." -- Mike Memoli

9:38pm -- Well, for now I am going to call it a night. Tonight in many ways gives more questions than answers. I think the biggest one is: Are there other Democratic Senators in trouble that we don't know about yet? I wonder how Evan Bayh, Russ Feingold and Patty Murray are doing. Their opponents are all pretty obscure (and Feingold's opponent has legal troubles), but their states are all a lot more Republican than Massachusetts. Recruiting over the next few days should be interesting, as I'm guessing there's a lot of state Senators out there who think they could be the next Scott Brown. - Sean Trende

9:36pm -- Spin cycle on full blast: "We only had 59 senators to start with, and that's what we have now." That was Howard Dean on MSNBC, noting Arlen Specter's party switch. - Kyle Trygstad

9:34pm -- Is there any doubt who the GOP asks to deliver the State of the Union response? Brown seems like a slam-dunk choice. -- Mike Memoli

9:32pm -- It's still hard to figure out how Coakley lost. She appeared to be hitting her targets or even doing better in places like Somerville, Cambridge, Boston, etc., and she did well in a lot of the outer suburban towns. She didn't look so strong in the more blue collar towns; that probably made the difference -- Sean Trende

9:31pm -- GOP reax from RGA chair/Gov. Haley Barbour: "On the heels of Chris Christie's win in New Jersey's gubernatorial race, Scott Brown's breakthrough in Massachusetts proves that Republican candidates can be successful throughout the Northeast and across the country this fall." -- Mike Memoli

9:28pm -- Reaction and spinning begins. First to bat is DCCC chair Chris Van Hollen. "House Democrats have been preparing since day one last year for what we knew historically would be a very challenging election cycle. After winning five straight competitive Special Elections, the DCCC knows first hand how difficult they are and we are not taking anything for granted this cycle."

DSCC chair Robert Menendez: "“In the days ahead, we will sort through the lessons of Massachusetts: the need to redouble our efforts on the economy, the need to show that our commitment to real change is as powerful as it was in 2008, and the reality that we cannot take a single thing for granted and cannot afford even a second of complacency." -Kyle Trygstad

9:23pm -- Scott Brown's daughter Ayla, of American Idol fame, just announced to the ballroom that Martha Coakley conceded. The crowd exploded -- Mike Memoli

9:21pm -- AP calls it. Coakley has apparently called Brown and conceded. With 71% in, Brown leads 53 to 46. - Tom Bevan

9:19pm -- Here's a question: Would Rep. Michael Capuano have fared any better in the general than Coakley. Remember what he told the House Dem Caucus when he returned to Congress after losing the primary: "You're screwed." -Kyle Trygstad

9:18pm -- The Boston Globe reports that Coakley has called Brown to concede the Senate race -- Mike Memoli

9:14pm -- A bit of history: only 2 states have had all-Democratic Senate delegations longer than Massachusetts: Hawaii (since 1977) and West Virginia (since 1959). - Mike Memoli

9:08pm -- Mitt Romney, speaking on Fox News from Brown HQ: People are responding to the "attitude of arrogance" from "neo-monarchists" in Washington -- Mike Memoli

9:05pm -- Ouch. O'Brien beat Romney 67%-29% in working class Fall River. Coakley was 57%-41%. Double ouch. New Bedford is 59%-39% Coakley. These working class towns are making up for relatively mediocre Brown showings in the suburbs. - Sean Trende

9:03pm -- With close to 60% in, Brown is up 53%-46%. Boston is 1/3 of the way in. Coakley's going to start running out of votes soon. - Sean Trende

9:00pm -- Good county-by-county results map at the NYT. - Tom Bevan

8:51pm For what it's worth, Bostonian Howie Carr says on Fox that Brown is a lock to win. - Tom Bevan

8:50pm -- Wow, Dracut loves them some Scott Brown. 70%-30%, versus 59%-36% for Romney. - Sean Trende

8:48pm -- So much for Joe Kennedy as a spoiler. He's getting barely 1% of the vote right now. Cook Report's Jennifer Duffy points out on Twitter: There are NO uninformed voters turning out -- Mike Memoli

8:47pm -- About 1/4 of precincts are in, and Brown is back down to a 52%-47% lead. Boston is about 10% in now, and Coakley is still running behind there. I wish I knew where these precincts are located. -- Sean Trende

8:46pm -- Ben Smith obtained an internal Coakley memo today, blaming national Democrats for the loss. It's basically talking points for why the (potential) loss is not the campaign's or candidate's fault. -Kyle Trygstad

8:44pm -- With 21% in, it is a 53%-46% Brown lead. Brown is running a few points ahead of Romney's total out in Woburn. - Sean Trende

8:40pm -- Interesting. Boston precincts are starting to trickle in. With about 5% reporting, Coakley's up 51%-48%. - Sean Trende

8:39pm -- 363 of the 2168 precincts are in, and Brown is holding steady at a 52%-47% lead. - Sean Trende

8:39pm -- The Doug Flutie Band is playing at Brown headquarters in Boston. The candidate himself is watching returns in his hotel room. Also on site: Mitt Romney, who figures to capitalize on a Brown win. - Mike Memoli

8:36pm -- Numbers. Blurring. Together. In Concord, Brown is running well BEHIND Romney. 61%-38% for Coakley versus 48/45 Romney. Incidentally, the focus on Romney's coalition is because that's the only close race that CNN has up on its website. Quick access to data. Obviously, if Brown overperforms in Boston or Worcester, it might not matter if he runs behind Romney in the 'burbs. -- Sean Trende

8:33pm -- Nancy Pelosi told reporters earlier today that Congress will pass health care no matter what happens in Massachusetts. -Kyle Trygstad

8:30pm -- The Caucus reports that "Democrats were studying turnout models and disappointed by what appeared to be lower-than-expected turnout in minority precincts, which typically trend Democratic." - Tom Bevan

8:28pm -- Romney won Sudbury 58%-37%. Coakley just carried it 51%-48%. 52%-47% Brown with just under 10% in. But Boston hasn't started reporting yet. - Sean Trende

8:27pm -- Liberal Rep. Anthony Weiner (D-N.Y.) says just the possibility that Coakley could lose should be enough of a sign that Dems should step back and say the party hears what the voters are saying. - Kyle Trygstad

8:26pm -- In suburban Framingham, Brown is running 57%-42%, which is a bit ahead of Romney's 2002 showing. Only about half the precincts are in, though. - Sean Trende

8:23pm -- Incidentally, Olbermann WAS joking about apologizing to Brown. - Tom Bevan

8:22pm -- With 4% in, it is down to a 52%-47% lead for Brown - Sean Trende

8:21pm -- In Concord, Brown is running well ahead of Romney. 61%-38% for Coakley versus 48/45 Romney. - Sean Trende

8:19pm -- Results are tricking in. With 36 precincts -- almost 2% ! -- Brown is still at 55%-45%. Ashland is in, giving Brown a 54%-45% lead. Romney won it 59%-36%. Unless Brown is putting together a different coalition than Romney's, he's in trouble. - Sean Trende

8:18pm -- County by county results here. - Tom Bevan

8:16pm -- Keith Olbermann about to issue apology to Brown on MSNBC. It doesn't appear he's joking. - Tom Bevan

8:15pm -- The town of Bolton is all the way in. It is 57%-42% for Brown. In 2002, it went 61%-32% for Romney. Not a great sign for Brown. - Sean Trende

8:14pm -- We have our first results. Scattered precincts in some smaller towns are showing a 55-44 Brown win. Seven down, 2,161 to go. By the way, Massachusetts, like most New England states, reports by city, not county. That makes election analysis especially painful, unless you know the state really well. - Sean Trende

8:12pm -- An election-day poll from Rasmussen found that 22 percent of Democrats voted for Brown. A hint of good news for Coakley: among those who decided in final days, she leads 47-41% -- Mike Memoli

8:07pm -- High turnout across the state which most think benefits Brown but could also theoretically be helping Coakley as well. - Tom Bevan

8:03pm -- What will be the bigger headline tomorrow in Boston? Coakley/Brown Wins. Or Red Sox Re-Sign Jonathan Papelbon. --Kyle Trygstad

8:01pm -- No election would be complete without charges of ballot tampering. - Tom Bevan

7:56pm -- The polls haven't even closed yet but already we've heard some talking heads put "Scott Brown" and "2012" in the same sentence (and not because he'd have to run for re-election then). Politico (link) flags this item putting Brown as a 20-1 shot to win the GOP nomination. And for the record, by election day 2012 Brown will have served in statewide office for longer than Sarah Palin (depending on when Democrats would seat him, of course) -- Mike Memoli

7:55pm -- As we wait for the polls to close, it's worth taking a moment just to marvel at the fact that it is worthwhile to conduct a liveblog of the Massachusetts special election. Obviously the polling has been kind to Scott Brown, but predicting turnout in these elections is notoriously difficult. This should be a fun, fascinating night. - Sean Trende

7:53pm -- The Coakley campaign called a press conference earlier today to raise voters' awareness of voting irregularities -- ballots pre-marked for Brown. However, Sec. of State William Galvin said only a half-dozen around the state were found. The Brown campaign called them "reckless accusations." - Kyle Trygstad

7:48pm -- The polls don't close for another 10 minutes or so, but ABC News reports that Evan Bayh is warning his fellow Democrats that ignoring the lessons of the Mass race could “lead to even further catastrophe” for his party. - Tom Bevan

7:45pm -- Welcome to what is bound to be an exciting evening. - Tom Bevan

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