Tom DeLay thinks he's a Marxist (if only mewls my subscription to New Left Review), McCain isn't sure he's not a socialist, and everyone else in America agrees Obama's a partisan liberal Democrat despite his sentimental post-partisan effluvium. The evidence for this assessment rests heavily on an elaborate ranking system devised by the magazine National Journal — sort of the Zagat for congressional voting (Barbara Boxer's "romantic" yea for this "controversial" resolution to "carve up" Iraq makes her a "fire-breathing elitist gorgon.") It named Obama the "Most Liberal Senator" in 2007. Except that its methodology is cracked, according to Josh Patashnik at the New Republic. For one thing, a decisive factor in the magazine's evaluation is how many votes a lawmaker has missed, and Obama's actually not been truant enough:

First, Obama missed a lot of votes—a third of the 99 votes National Journal included in its analysis. A large group of liberal Democratic senators is separated by just a few votes, and by missing so many, Obama deprived himself of chances to rack up more "conservative" votes. He didn't take public stances on all the votes he missed, but it's clear there are some where he would have strayed from the liberal line, knocking himself off the "most liberal" perch. He missed the December 4 vote on the free trade agreement with Peru, for instance, but publicly supported it, which would have counted as a "conservative" vote.

If you miss more than half the votes pertaining to any of the mag's big three categories — economic, foreign and social policy — you aren't even ranked. McCain isn't for this reason, which means that Obama's notoriously lax attendance in the Senate wasn't lax enough to spare him from the misleading label of being essentially a P.J. O'Rourke caricature of a Washington lefty. Also, the rubrics "liberal" and "conservative" are bogus, too. Vote for a bill authorizing research into nonembryonic stem cells — even if you support research into the embryonic kind — and you're counted "conservative" for a day. [TNR]