Thomas Riehle of RT strategies passes along a hierarchical vote analysis he completed for the Cook Report; he first breaks down the vote for each candidate into seven categories measuring enthusiasm, and then he evaluates how that "hiearchy of intensity" holds up across 50 different subgroups of voters.

Since March, Obama has picked up 15 percentage points worth of support from "strong Democrats," 31 points among women aged 18 to 39, and 14 points among those without college education. McCain has picked up support among voters aged 50-64, women aged 40 to 56 (17 points -- he leads Obama overall by four points now), and independents who aren't leaners. But he's lost support among conservative Republicans -- down to 81% in this poll and Republican women -- 75% support him.

The demographic contours of Obama's base are clear: African Americans, 18 to 34 years olds, younger women, less educated (a shift since the primaries), and among voters on the Pacific Coast, the Midwest and the Great Lakes regions.

McCain has an edge in the South -- and really nowhere else. He and Obama are running (roughly) equal in the West, the farm-mountain region and even the Northeast. McCain has a 16 point edge among evangelical voters; Obama has a 19 point edge among voters who aren't born again. He's getting about one in four former Clinton voters and ties Obama among women with college degrees.

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