The liberals might gnash their teeth and complain about Obama's supposed cave-in to the Republicans on the tax cuts. But ignore all this talk about some primary challenger to Obama. Who would it be? Howard Dean? Please. The guy couldn't win in a primary running against John Kerry, for gosh sake! Russ Feingold? He couldn't win his own state. That's rather basic. If the people who knew him the best didn't want him any more, it would be hard enough for him to succeed in an open election year, much less against an incumbent.
But remember, Obama is going to get the African American vote. That's key in the Democratic primaries. Labor will be with him. He has the organization and the media spotlight.
And then remember that he will be able to say to the Democratic primary voters that he is their only hope to hold the White House against whichever horror that those evil Republicans nominate. That will be a sufficient threat to bring the progressives home with their tails tucked between their legs.
And he'll be able to remind the progressives of all the wonderful things he's done for them - health care, bureaucratic provisions to protect labor, liberal judicial appointees, stimulus goodies, etc. Obama might be graceless in how he tries to convince the liberals of all that he has done for them, but he's got the arguments on his side. They're just whining not to have gotten every single thing that they ever wanted, but anyone who understands politics understands how much Obama has done that progressives should be happy about.
The only way that Barack Obama wouldn't be their candidate in 2012 is if he himself decided that he has had enough of trying to govern all of us ungrateful wretches who fail to appreciate how truly awesome he is.