The latest McCain campaign ad accuses Obama of a single, supposedly disqualifying, crime: Being liberal. But after this election (assuming Obama holds onto his lead and wins) Republicans are going to finally come to the realization that "liberal" isn't the dirty word it once was.

It is partly a generational issue. Baby boomers have been conditioned since the culture wars to instinctively know what "being liberal" means. And conservatives were very successful at making sure that connotation was negative. The label has been so tainted that for years conservatives have won elections by accusing their opponents of being liberal, and liberals have won elections by portraying themselves as anything but.

But yesterday's politicians assume those negative connotations have carried over to Gen X and Y, and I'm not so sure they have. When the under-30 crowd hears, "OMG, he's a liberal," rather than a knee-jerk revulsion, the response seems to be, "So what?"

Forget the fact that these generations tend to actually be more liberal. Even the independents are simply working on different definitions and don't make the same assumptions. The cultural issues that helped Republicans initially define the word have faded, and younger voters don't instinctively know why being liberal is bad when it comes to healthcare or the economy or foreign policy. If Republicans really want "liberal" to be a dirty word, they're going to have to redefine it for post-culture war voters.

For those of us who became politically aware under either Bill Clinton or George W. Bush, liberals haven't the bad guys. Liberals didn't start an unnecessary war in Iraq. Liberals didn't mishandle Hurricane Katrina, or drastically expand programs to spy on Americans, or earn us a reputation as torturers. And liberals aren't the ones denying our friends basic rights based on their sexuality.

They may have been complicit, but they weren't the primary culprits. If you want to find a negative label that instantly turns off Generation X and Y voters, don't call your opponent a liberal. Call him a neoconservative.