Hope and Change has struck the Democratic Party in a big — and unexpected — way.  Gallup analyzes its poll data from 2010 on party affiliation to look at the shift in each state, and the news is almost uniformly bad for Democrats.  Almost every state has had a decrease in voter affiliation for Democrats, most of those significant, and the number of solidly-blue states has been cut in half:

Gallup’s analysis of party affiliation in the U.S. states shows a marked decline in the number of solidly Democratic states from 2008 (30) to 2010 (14). The number of politically competitive states increased over the same period, from 10 to 18, with more limited growth in the number of leaning or solidly Republican states. …

Even with Democratic Party affiliation declining during the past two years, Democratic states still outnumbered Republican states by 23 to 10 last year, and there were 14 solidly Democratic states compared with 5 solidly Republican states. …

Looking more closely at the changes in state party affiliation since 2008, only one state moved from a Democratic positioning to a Republican positioning — New Hampshire, which was solidly Democratic in 2008 but now is considered leaning Republican. Alabama, Kansas, Montana, and South Dakota moved from a competitive designation to solidly or leaning Republican status. A total of 12 states — Arkansas, Colorado, Florida, Indiana, Louisiana, Maine, Missouri, Nevada, Oklahoma, Tennessee, Virginia, and Wisconsin — shifted from solidly or leaning Democratic to competitive. No states have moved in a more Democratic direction since 2008. (A listing of each state’s classification for 2008, 2009, and 2010 is available on page 2 of this report.)

So much for 2008’s supposed political realignment.  Barack Obama now appears to have profited from Bush fatigue more than any move of the country to a center-left position on the political spectrum.  Most states show Democrats losing ground, even in the 14 states that are solidly Democratic.

That gives Obama some bad portents for his 2012 re-election campaign.  It also puts Democratic control of the Senate after the 2012 elections an even more remote outcome.  In key states, Democratic incumbents face tough fights — or where some Democrats have retired, an even tougher fight for an open seat.  Using Gallup’s historical tool to look at these key states, we can track the problem on both levels:

Forgive the order in which I entered these, but do look at the impact of these affiliation changes in key states.  In five states that Obama won in 2008 (VA, IN, FL, WI, OH), the change in party affiliation change outstrips Obama’s margin of victory — which would result in a flip of 81 electoral votes.  Adding in Pennsylvania, where the difference is under a single percentage point, Obama loses 101 EC votes in the next election — which would result in a Republican victory.

Republicans also look strong in races with Democratic incumbents, especially in Wisconsin and Ohio.  Florida looks promising, and even in Pennsylvania, the GOP has closed the gap considerably heading into 2011.  Republicans barely lost in Washington in 2010m but may have enough momentum to seriously challenge Maria Cantwell for her open seat.  Claire McCaskill looks especially vulnerable in Missouri.

Much will depend on the GOP’s ability to deliver on their promises in the House this year for fiscal discipline, and the Democratic attempts to subvert and thwart those.  If they can accomplish that, Republicans may pick up even more momentum into 2012 and put more Senate seats — and Electoral College votes — in play.

Update: I should have noted it above, but the EC totals I use are the post-Census numbers that will be in play in 2012.