The current Electoral College system is guaranteed to provide more opportunities for contentious recounts than a national popular vote -- nearly every close election could change hands with a relatively small shift of votes in one or two states, but rarely would one of those close elections be seen as likely to change with a national recount. Only once since the 19th century has a national popular vote been decided than less than a half million votes -- and even then the margin was 120,000 votes, far outside what might change in a recount. There is far more chance of contentious recounts that swing the election when there are 51 separate winner-take-all contests for electoral votes.
Consider this statement provided this week by University of Pennsylvania professor Jack Nagel, who is writing a paper on this subject to be published later this year.
"Defenders of the Electoral College often attempt to turn the Florida 2000 fiasco into a reason for rejecting the direct vote alternative. Granted, they say, Florida was a national nightmare, but the agony would be far greater if such a dispute extended over the entire nation. They ignore the obvious answer: The national vote in 2000 was not close enough to dispute, nor has the popular vote been that close in any recent election. Using any reasonable assumption about how close an election must be for recount demands to arise, the likelihood of disputes is greater under the Electoral College than it would be in a national direct election. This can be demonstrated both mathematically and historically. Over the full period when most states permitted citizens to vote for president (1828-2004), disputable elections have been two to five more frequent under the Electoral College than they would have been for direct popular elections, depending on the thresholds assumed for disputability in electorates of varying sizes."