Republican politics

If the stimulus is effective and the economy recovers fairly quickly, Republicans will be in the unenviable position of arguing that the stimulus actually slowed recovery and that Democrats should be punished for dragging out the recession--that Republicans would have handled the crisis better. Here's how that dynamic sounds from the mouth of a gibbering baboon Karl Rove:

[I]f Republicans predict economic doom, they will overplay their hand. The Democratic stimulus will slow recovery, but not stop it. Recessions don't last forever and, if history is a guide, sometime late this year or early next the economy will rebound on its own.

This is sort of comically detached from reality, but buried in there is, I think, the Republicans' real strategy--to go the full Limbaugh and argue that, while the economy may recover, the stimulus is a failure as of yesterday. It's sort of the best they can hope for. If the economy recovers, they're still screwed, but at least the Democrats will have to work back from a lower baseline of support than they would have in absence of the anti-stimulus propaganda.