Rasmussen's tracker has Romney up by 7, and if we factor in a 3.9-point house effect as determined by Nate Silver (and I think Rassy has partially fixed their model since 2010), this result would still be consistent with Romney up by 3 nationally.
Yes, but all other polls have Obama winning nationwide.
All other polls weren't conducted after Obama's gay marriage announcement (which, sadly, seems to have hurt substantially).
What evidence is there for this?
EDIT: Unless I'm much mistaken there's a Rasmussen tracker, which.... no, and a Dick Morris poll, which people should be banned for posting. Not exactly a wealth of evidence, wormy.