In our opinion, Brad Coker at Mason-Dixon continues to do the best state polling. Today he has released a basket of eight Senate polls for MSNBC in the competitive Senate races that will determine control of that chamber (Maryland is the only race which might be competitive where he did not poll).

I spoke with Coker this morning, and he breaks these races down into three distinct groups. The first group is Pennsylvania, Ohio and Rhode Island, which he describes "as slipping away from the Republicans." RCP has all thee of these races as "Leans Democrat," and right now these look like three pretty firm pick ups for the Democrats.

The next group is Montana, New Jersey and Missouri - all races where Mason-Dixon shows the Democrat ahead by three points. Coker describes these three as "leaning Democratic" and, interestingly, he ranks New Jersey as the most likely state Republicans could get out of this group, followed by Montana, and then Missouri. Both New Jersey and Missouri have been ranked Toss Ups for some time by RCP, and today on the back of the Mason-Dixon poll we are moving Montana to a Toss Up, one week after downgrading Burns from the #2 most vulnerable incumbent to #4.

I don't know that I agree with Coker's order of vulnerability in these three, but I don't take it as good news for the GOP that he ranks the seat in Missouri as the least likely of the bunch for the GOP to win. Since Mason-Dixon's last survey in these three states, Missouri has moved 3 points toward the Democrats; Montana has moved 4 points toward the GOP, and New Jersey in unchanged. I suspect Republicans will win one of these three states barring a complete GOP meltdown. Coker seems to think from where things stand today the odds favor the Democrats taking all three.

Finally, we have the two seats in Virginia and Tennessee. Coker sees the Republicans almost having the same edge here as the Democrats have in the last group (MT, MO, NJ). Mason-Dixon's work has Bob Corker ahead in Tennesse by 2 points and George Allen ahead in Virginia by 4. Coker feels that if Republicans were to lose either one of these races he sees little chance they could win in Montana, New Jersey and Missouri - which effectively means they would lose the Senate. As a corollary, if the GOP could win one of the MT, MO, NJ group, Coker sees very little chance they would lose in Virginia or Tennessee. I tend to agree with that characterization, though the ethical troubles of Menendez in New Jersey makes that race a bit of an independent situation.

At the end of the day, Coker sees the evidence today pointing to a 50-50 tie with Republicans retaining control, this is also where the latest RCP Senate Averages place the Dem pickup. . I agree that the GOP maintains an edge in Virginia and Tennessee and thus is likely to retain control, but as I said earlier, I suspect Republicans will pull out one of three in Missouri, Montana and New Jersey to keep their losses to four and a 51-49 edge in the Senate. This also happens to be where the current InTrade markets peg the Senate playing field as well.

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