Nate Silver over at Five Thirty Eight flags voteview.com, which uses what he considers to be a reasonable, rigorous and intuitive methodology for ranking the liberalism or conservatism of senators. Unsurprisingly, Obama comes out as slightly left of the Democratic center, but far from the sensational "most liberal" position awarded him by National Journal. But guess who was within the ten most conservative senators last year, according to Voteview? John McCain. Silver notes:

In the 107th Congress, however, McCain was quite moderate. Voteview doesn't have rankings before the 107th, so I'm not sure whether there was some permanent change in McCain's political philosophy on or around 2003 (perhaps coinciding with the start of the Iraq War) or whether it was his behavior in the 107th that was unusual (perhaps he took some pleasure in being a thorn in President Bush's side after having lost the primary to him). But this is more evidence for the notion that the 2008 version of John McCain is a very different politician than the 2000-2002 version of John McCain.

Voteview ranks McCain as the second most conservative senator in the 109th Congress, a more exciting find from the Democrats' point of view. But the rankings for the 109th look a little less intuitively right than those for the 110th to me -- the site rates New Hampshire's John Sununu as the third most conservative while putting wingnutty Rick Santorum slightly left of the Republican center. I'd have to think more about what votes happened in the 109th to have faith in McCain's hard-right rating. But I think the general trend Voteview and Silver highlight is a sound one: By the hard numbers, McCain of late has been a much, much more conventional Republican in his voting than his maverick reputation would suggest. Votes aren't everything, and they aren't a perfect predictor of how someone would behave in the executive branch. I do give McCain credit for sticking his neck out rhetorically for bipartisanship on immigration -- it was a big risk in places like South Carolina, and a meaningful risk. But he simply hasn't stuck his neck out when it comes to his ballots.

--Eve Fairbanks