Bloomberg makes the case that early voting in a volatile race has it downsides.  For example:

Debates have been integral to the campaign this year, yet more than 447,000 Floridians cast ballots before the Jan. 26 debate in Tampa, the last before the state’s Jan. 31 primary. By the time the candidates took the stage that night in Jacksonville, 11 percent of Florida’s 4 million registered Republicans — and a higher percentage of actual voters — had already voted.