Who might ultimately benefit is still not clear. It depends upon the Republican's response, their actions, liberal spin and media support for one side or the other.
But, with the polls concerning public reaction to this action of Obama's, it's clear he is on the losing end. Couple that with the fact that every Democrat will be affected by Obama's Presidential record...especial the Democratic nominee for President...you can be sure this stuff is going to affect them. The Republicans will try to make sure of that.