On Thursday, Kos posted a diary listing the states that fell into three categories of shift in voting margin for president from 2004 to 2008: those that had shifted to the GOP, those that showed no shift, and those that shifted to the Dems by 10 or more points. I took those states and compared them to the Gallup Party ID shifts from 2002 to 2008, and this is what I came up with:
There were 12 other states which also shifted Democratic by 10 or more points in party ID from 2002 to 2008. This is the strongest indication that the partisan vote shift over 6 years significantly exceeded the presidential vote shift from 2005 to 2008.