With the addition of Washington Gov. Jay Inslee and former Colorado Gov. John Hickenlooper, 14 Democrats are now running for president.

Though Hillary Clinton, Michael Bloomberg and -- lest we forget -- Oregon Sen. Jeff Merkley this week demurred, the Democratic presidential field is likely to be even larger than the GOP’s rambunctious 17-person battle in 2016. Former Vice President Joe Biden, Ohio Sen. Sherrod Brown, Montana Gov. Steve Bullock, former Virginia Gov. Terry McAuliffe, Texas Senate wünderloser Robert Francis O’Rourke and several congressmen you’ve never heard of could still jump into the race.

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In the resulting battle, expect the unexpected. The Democrats’ problem goes beyond the number of candidates. Changes to the electoral calendar and rules have introduced further complications.

For one thing, the first Democratic debate is this June, while the first Republican debate in 2015 was Aug. 6. Planning for as many as 20 candidates, Democratic National Committee chairman Tom Perez says his party won’t follow the GOP in having an adult debate with the front-runners and a separate kiddie debate for those lagging in the polls. We’ll see if Mr. Perez has any secret sauce. Otherwise, a 20-podium stage may prove tough to manage. At minimum, some candidates will try to stand out by making (a) harsh attacks on fellow Democrats, (b) over-the-top assaults on President Trump, and (c) radical proposals to please the party’s hard-left base. Expect a few 2020 hopefuls to hit the trifecta.

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