If this poll from Public Policy Polling is any indication, a fair number of Republicans have convinced themselves Barack Obama won re-election with fraud and other nefarious efforts:
49% of GOP voters nationally say they think that ACORN stole the election for President Obama. We found that 52% of Republicans thought that ACORN stole the 2008 election for Obama, so this is a modest decline, but perhaps smaller than might have been expected given that ACORN doesn't exist anymore.
Kevin Drum calls this evidence of the "Fox News effect"-the process by which conservative propaganda outlets convince their viewers of things that just aren't true-but I think there's a better, more charitable explanation. In short, a large number of Republicans don't like President Obama, and when offered a chance to endorse something that signals that dislike, they did it, even if the "something" is absolutely insane.
I doubt that-if you pressed respondents on their answers-49 percent would say that the election was stolen. But if I'm wrong, we have a serious crisis of political legitimacy on our hands.