2016’s Lopsided Fields In 2016, Democrats fielded the fewest number of candidates since 2000, when Vice President Al Gore won the nomination. The Republican field at its peak had 17 major candidates, including eight current or former governors and five current or former senators.

The Era of the Long Campaign The 2012 Republican primary race lasted well into the spring, as candidates backed by wealthy super PAC donors were able to hang on longer than they might have otherwise. But the race was short compared with the 2008 battle for the Democratic nomination, when several candidates announced early, in part because to the early primary schedule, and Hillary Rodham Clinton and Barack Obama remained locked in a tight battle for delegates until June.

The Thinnest Contested Primary in Recent History The 2000 Democratic primary field was the smallest in modern history, with Vice President Al Gore winning every primary contest over his only major competitor, Senator Bill Bradley of New Jersey. The Republican field that year had a series of early departures, with five major candidates leaving the race by October 1999.

Early Primaries Begin to Present Key Test Historically, candidates would remain in the race until the conventions, but by the 1980s, candidates who underperfomed in the Iowa caucuses and early primaries began to withdraw soon after. While the eventual Democratic nominees entered the race at least 79 weeks before the election, the Republican nominees were relatively late to announce.