This is a tough one to determine! OVERALL it appears that American approval of same-sex marriage is on the rise, but the African American group (one of Obama's larger support groups) is traditionally pretty against same-sex marriage. I think this issue could go either way at this point. It could make Obama look good in the eyes of young, progressive Americans, or make him look like a "flip-flopper" to the Republicans. He has to play this one pretty carefully!

I think it will definitely motivate people on both sides of the issue. I think he's assuming that since a majority of Americans are on board in some surveys that it will translate to election support. But, it may also serve to drive some of his opposition to spend more, work harder, etc. to see him unseated.

Time will tell, but it is an interesting question that will play out.

He will for sure attract more votes specially the younger crowd no matter if they are gay or not gay. This revitalizes his campaign. Bottom line is he will be able to attract more votes.