House Democrats have banned all budgetary earmarks to private companies, pledging to end the corruption that associated with the earmarks process. But I don't think this has a thing to do with earmarks or corruption. Given that Senator John McCain's focus on earmarks during his 2008 presidential campaign seemed to generate more mockery than support, it's hard to believe that Democrats really see earmarks as a big issue worth championing. More likely, I think, is that Democrats are trying to distance themselves from the hugely important but politically disastrous American Recovery and Reinvestment Act, otherwise known as the stimulus.

The stimulus appears to have played a crucial role in slowing or reversing the recession. But, with unemployment still hovering near 10 percent, it's not seen as any great savior. Polls show support for the stimulus still falling over a year after its February 2009 passage. As George Packer argued in the New Yorker, the stimulus has been undersold. Its effects have been productive but, by design, so subtle as to be nearly invisible. The popular opposition to the stimulus, however unfounded, is now so entrenched that Democrats may have concluded their opportunity to sell it is long gone.

Foreseeing the Republican strategy of running against the stimulus (and its hated cousin, the bailouts), Democrats are trying to beat them at their own game. The stimulus has been accused of being stuffed with earmarks, and of course that's true, because one third of the stimulus is designed to spend money on things like "shovel-ready" infrastructure projects. A lot of this spending has to be applied for, but some of it was singled out by legislators for especially ripe projects. That's likely contributed to the stimulus' success, but it doesn't change that the stimulus is unpopular and earmarks are unpopular. So, by making a lot of noise about opposing earmarks, Democrats are in a sense trying to run against their own stimulus. The idea is to defend against the Republican anti-stimulus electoral strategy and maybe even to make that strategy their own.

Republicans, for their part, have responded by proposing a ban on all earmarks, including for non-profits and local governments, which could block earmarks on things like infrastructure and school spending. This wouldn't retroactively stop the earmarks already designated in the stimulus, but it would probably make the Democratic goal of a "jobs bill" more difficult by limiting spending opportunities.

There's an opportunity for this to turn into a wider debate that could get to the ironic truth about earmarks: Everyone talks about hating them, and in truth they are a frequent source of "pay-to-play" corruption. But sometimes earmarks are just federal spending on local projects, which can be good for the targeted communities and for overall economic growth. But that's a difficult case to make, and President Obama, when challenged by McCain on earmarks during the presidential race, never seriously tried to make it. If Democrats once again give in to the GOP narrative that all earmarks are bad, they'll risk the anti-stimulus political backlash all over again come November.