Median voter theory

The median voter theory suggests that candidates will try to appeal to the median Democratic or Republican voter to win the nomination, and then try to appeal to the median general election voter (Democratic + Republican + Independent) to win the November election. Charles Krauthammer is chonicling Obama's move to the center:

In last week's column, I thought I had thoroughly chronicled Obama's brazen reversals of position and abandonment of principles -- on public financing of campaigns, on NAFTA, on telecom immunity for post-Sept. 11 wiretaps, on unconditional talks with Mahmoud Ahmadinejad -- as he moved to the center for the general election campaign. I misjudged him. He was just getting started.

Last week, when the Supreme Court declared unconstitutional the District of Columbia's ban on handguns, Obama immediately declared that he agreed with the decision. This is after his campaign explicitly told the Chicago Tribune last November that he believes the D.C. gun ban is constitutional.

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Obama's seasonally adjusted principles are beginning to pile up: NAFTA, campaign finance reform, warrantless wiretaps, flag pins, gun control. What's left?

Iraq. The reversal is coming, and soon.

Two weeks ago, I predicted that by Election Day Obama will have erased all meaningful differences with McCain on withdrawal from Iraq. I underestimated Obama's cynicism. He will make the move much sooner. He will use his upcoming Iraq trip to finally acknowledge the remarkable improvements on the ground and to formally abandon his primary season commitment to a fixed 16-month timetable for removal of all combat troops.