From NBC's Mark Murray
National Journal magazine is reporting that Obama was the most liberal senator of 2007, according to the vote ratings it does every year for members of Congress. Clinton, meanwhile, ranks as the 16th most-liberal senator.
But a bit of context here: National Journal used 99 Senate votes in 2007 as the basis for its rankings, and because he was on the presidential campaign trail, Obama missed a third of those votes. (According to the magazine, Obama voted the liberal way 65 out of 66 votes. Clinton, meanwhile, voted the liberal way in 77 out of her 82 votes).
National Journal's vote ratings became an issue in the 2004 general election, when Republicans used the magazine's ranking of John Kerry as the most liberal senator of 2003 to label the then-Democratic nominee as the "most liberal senator" -- even though that was his rating for just that one year, when (like Obama did) he missed quite a few Senate votes due to being on the presidential campaign trail.
As National Journal's editor wrote back then, "[O]ur magazine -- or, more precisely, our annual congressional vote ratings edition -- has become a Republican talking point in the 2004 presidential campaign. And that's been a fascinating, and disconcerting, experience. Fascinating because we're more used to being cited in congressional hearings than on the Today show. Disconcerting because the shorthand used to describe our ratings of Kerry and Edwards is sometimes misleading -- or just plain wrong."
Indeed, while Obama ranks as the magazine's most liberal senator of 2007, his ranking was 16th in 2005 and 10th in 2006.
Another question that might come up is why the magazine released its voting ratings now -- just days before Super Tuesday. In fact, the magazine says it full congressional ratings won't come out until March. But, according to the editor in a Q&A published in the magazine: "Back in December, we decided that we would publish the ratings of the presidential candidates as soon as they became available, rather than wait until our annual Vote Ratings issue on March 8. We thought it would be irresponsible to keep those scores under wraps during the height of the presidential primary season."
As for McCain, the magazine says that he didn't vote frequently enough in 2007 to get an overall rating. Per National Journal, "He missed more than half of the votes in both the economic and foreign-policy categories. On social issues, which include immigration, McCain received a conservative score of 59."
And like with Obama's overall liberal score, rivals and critics could possibly seize on McCain's social rating....
Full disclosure: This reporter worked and wrote for National Journal from 1997 to 2003.