Just a week ago, the Washington Post ran a lengthy piece on President Obama’s sometimes strained relationship with LGBT and immigration reform activists, a story that featured numerous accounts of Obama’s pushback against activist demands for action:

“The president grew visibly frustrated as each successive advocate spoke. He said that … he sympathized with their concerns but that he did not have the legal authority to stop deportations.”

That was in March of 2010, more than two years ago. And of course he had the power then that he has today. But this afternoon he will step forward and announce a dramatic revision to immigration enforcement policy that DREAM Act supporters have been pushing for since his election. So what changed?

One change is that the DREAM Act itself died. It passed the House and Senate late in 2010, and again in 2011, but was killed by a Republican filibuster both times. By the end of 2011 it was clear that past GOP supporters of the bill weren’t going to budge anytime soon. It’s understandable that Obama didn’t want to muddy the DREAM Act waters with unilateral action while the bill still stood a chance of passage. It’s been clear for more than a year that the DREAM Act wasn’t happening, though, and Obama hasn’t acted.

Today’s current shift likely has two sources.

First, there’s the upcoming election. The DREAM Act is broadly popular with the American people, and particularly so with youth and Latinos. As I noted on Twitter earlier today, “stop being a douchebag” can be an effective re-election tactic. And because this policy is unlikely to be extended by a Romney administration, this isn’t just a rhetorical gesture or a policy pivot — it raises the stakes in November.

There’s another angle on the timing of the announcement too, though. For the last week, DREAM-eligible young people have been staging occupations at Obama campaign offices, first in Colorado and then in Michigan and California. Because the demonstrators were themselves undocumented immigrants, an administration decision to remove and arrest them would have subjected them to possible deportation, making the decision of how to handle the protests a delicate one. With today’s announcement, that decision goes away, as does the possibility that the occupations could spread to more politically problematic states — Florida, say, or Arizona, or the campaign’s national headquarters in Illinois.

What we’ve seen today, in other words, is new proof that you shouldn’t listen when an elected official tells you his hands are tied, as well as evidence of the power of electoral organizing combined with creative direct action.