Last year, I blogged about some research that Michael Heaney and I were doing on the anti-Iraq War movement. I found that the antiwar movement quickly collapsed after Obama’s election. Smaller crowds, less attention. The big finding is that Democrats stopped showing up after Obama’s inauguration. Based on 5, 398 surveys of street demonstrators, here’s the paper’s key chart:

In other words, once a Democrat gained power, Democrats stopped showing up to antiwar protests. If you want the full write up, read the paper, which has now appeared in Mobilization.

Bottom line: Social movements and parties rely on each other. Movements benefit when partisans appear because they can bolster their numbers. Parties use movements as platform for partisan grievances. But there’s a drawback, electoral victories mean that the rank and file will stop showing up.