I'll probably hold my nose and vote for centrist Democrats when the only viable opposition is Republicans. But, inevitably, I won't volunteer my time or donate money for centrist Dems.
And inevitably, Obama's centrism will probably harm the Democrats in November. Progressives naturally will be less willing to help the Democrats.
But when it comes to voting, I have to agree with Paul Krugman: "Just to be clear, progressives would be foolish to sit out this election: Obama may not be the politician of their dreams, but his enemies are definitely the stuff of their nightmares. But Obama has a responsibility, too.... He can't expect strong support from people his administration keeps ignoring and insulting" This quotation is from Krugman's Curbing Supporters' Enthusiasm , where Krugman enumerates some of the ways in which Obama has betrayed his base.
References
Democrats abandon Obama on Afghan war?
Oregon Democrats vote against war funding
The Republican plan to wreck the economy and then blame the Dems. Will it work?
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