Candidates would campain in nearly every state, too, forcing them to address everyones concerns (not just make empty transparent promises of 100 new Navy ships to Norfolk and Pensacola voters.) Elections have been getting tighter and tighter since 2000 but have been decided by two or three states for the past 20 years; that is ridiculous, and not terribly democratic. I think the last presidential rally in CA or TX was when Obama started his primary campaign in '08, and before that it was '04, when Kerry slipped over the border to North TX just to prove he was not scared to do so. It is little better in IL. No one takes Romneys ad buys and rallies in PA, WI, MI and MN seriously, but if it were done by CD they most certainly would, because all but the smallest states would be in play.

The one big downside is redistricting, which gets more partisan every decade. Whatever the flaws, one asset of winner-take-all state elections is that whoever wins a states popular vote wins the state. A gerrymandered presidential election is among the few ways to make a badly broken system worse. After all, the bulk of the problem is not the system itself, but the very same partisan electioneering that spawned gerrymandering. Mixing redistricting and presidential elections might well produce a perfect storm no one wants.

Omaha is a good example of both the benefits and detriments: Obama won it last time despite getting buried in Bob Doles home state, but after the 2010 census NE Republicans responded by carefully drawing CD boundaries in Omaha to make sure that NEVER happens again.