From his speech today at LULAC:

It's about all the people who are paying a price because of our broken immigration system; all the communities that are taking immigration enforcement into their own hands; and all the neighborhoods that are seeing rising tensions as citizens are pit against new immigrants. They need us to put an end to the petty partisanship that passes for politics in Washington and enact comprehensive immigration reform once and for all.

Now, I know Senator McCain used to buck his party on immigration by fighting for comprehensive reform, and I admired him for it. But when he was running for his party's nomination, he abandoned his courageous stance, and said that he wouldn't even support his own legislation if it came up for a vote. Well, for eight long years, we've had a President who made all kinds of promises to Latinos on the campaign trail, but failed to live up to them in the White House, and we can't afford that anymore. We need a President who isn't going to walk away from something as important as comprehensive reform when it becomes politically unpopular.

That's the commitment I'm making to you. I marched with you in the streets of Chicago to meet our immigration challenge. I fought with you in the Senate for comprehensive immigration reform. And I will make it a top priority in my first year as President - not only because we have an obligation to secure our borders and get control of who comes in and out of our country. And not only because we have to crack down on employers who are abusing undocumented immigrants instead of hiring citizens. But because we have to finally bring undocumented immigrants out of the shadows. Yes, they broke the law. And they should have to pay a fine, and learn English, and go to the back of the line. That's how we'll put them on a pathway to citizenship. That's how we'll finally fix our broken immigration system and avoid creating a servant class in our midst. It's time to reconcile our values and principles as a nation of immigrants and a nation of laws. That's what this election is all about.

Now, not to be too much of a stickler about petty partisanship and all, but Obama famously and repeatedly voted for a "poison pill" amendment that was instrumental in killing comprehensive immigration reform last year. Here are the lead paragraphs from Bob Novak's June 14, 2007 column:

Democrat Byron Dorgan, who seldom has tasted legislative success during 15 years in the Senate, scored a dubious victory last week. He was able to insert a poison pill into the immigration reform bill that aimed at emasculating the essential guest-worker program. The 49 to 48 vote that passed Dorgan's amendment included surprising support from two prominent first-term senators: Jim DeMint, a conservative Republican from South Carolina, and Barack Obama, a Democratic presidential candidate from Illinois.

Dorgan pushed his killer amendment by voicing the Great Plains populism of his home state of North Dakota, but the measure was the product of organized labor. DeMint, normally counted on to oppose anything with the union label, admittedly voted for the Dorgan amendment for the sole purpose of killing the immigration bill. Obama's vote was even more surprising, considering his participation in the closed-door bipartisan drafting of the immigration compromise that had secured a major change.