Fast Fix: Will Obama face a 2012 primary challenge?

Liberals are unhappy with President Obama. Vice President Joe Biden recently told the left to "stop whining".

Is the unrest within the party a recipe for a serious primary challenge to the president in 2012? And, if so, who might take on a race like that?

We answer all those questions -- and more -- in today's "Fast Fix" video below. Make sure to check out all of our "Fast Fix" videos here. And, if you have an idea we should tackle, send it to chris.cillizza@wpost.com.