Never have American voters re-elected a president whose work they disapprove of as much as Barack Obama's. Not that Mitt Romney can take much comfort — they've never elected a challenger they view so negatively, either.

Unless things change dramatically, this Election Day will mark a first, no matter who wins. The victor will be a sitting president with a slow economy, 8 percent-plus unemployment and an average Gallup job-approval rating below 50 percent. Or he'll be a challenger who isn't liked personally by a majority of the public and faces notable discord within his own party.