An Electoral College tie. It's the white whale of American elections: elusive, mythical and never realized. But could it finally happen this year? The likelihood that President Barack Obama and Mitt Romney will each net 269 electoral votes in November, instead of the 270 needed to win, is actually not so farfetched -- and for close observers of the Electoral College system, a tie would set off a wave of constitutional and political mayhem that would make the 2000 Florida recount seem like a tidy affair. Check out the CNN electoral map and calculator Election results in key states would...