What's the most appropriate measure for gauging decisiveness of a victory in a modern-day presidential election? Popular vote, as I know I thought in 2000? Electoral delegate margin, as the system might lead us to believe? Most swing states captured, as Bill Maher has suggested? The winner's performance in key demographic areas, like Obama's along non-white voters and white women?

Is there any simplistic, objective-ish way to figure the extent to which this win is a mandate? Or does it just not work that way?

My initial reaction is still that there are so many available interpretations, that to gauge the strength of the mandate behind any election is a matter of opinion and, to a large extent, persuasive ability. IE, how many ways are there to skin a cat, and do the victors still write history? That said, just the fact that two folksy euphemisms spring so quickly to mind here tells me I likely have a poor grasp on the requirements of a rigorous answer to this question.

Is it fair to suggest that we live in a post-decisiveness world? Obama crushed Romney in certain demographics, Romney crushed Obama in others. Collectively, they add up to about 50/50, but "50/50" suggests that any one person could've tipped blue or red, and that's not really the case.

That said, the majority of voters still hover around the center (and for the foreseeable future, slightly left). Most Romney voters aren't religious extremists or gun nuts; they just want a stronger economy or lower taxes. Most Obama voters aren't Socialists or welfare lifers; they just support civil rights and basic social programs. By going way right, Romney made it difficult for moderate voters to jump on board. Obama won by fishing where the fish are.

</folksy euphemism>

Coattails. Dude's were miles long.

Not sure I follow you. Obama's coattails were long? And somebody was riding on them? (And this makes it an especially big win or something?)