I doubt one candidate will lose the popular vote and lose the EC. That RARELY happens. It's happened something like two times in our countries history.
There way I see it is this: Romney leads VA, NC, and FL. Obama leads CO, NH, IA, WI, and I don't even consider MI and PA in play. If the election were held today, Obama wins with this map, and I doubt things will change until after the last debate, if they change at all:
The odds that Mittens wins the popular vote while losing the electoral college look like the highest they have been in any election in my lifetime. I put the odds (yes pulled out of my ass), at as high as 15%.
You do remember the 2004 election, when it looked like Bush might win the popular vote while losing the Electoral College? Or for that matter the 2000 election when Bush appeared to be in the same scenario (even though the scenario reversed on Election Day)?
