The District of Columbia presidential primary is the latest in the nation, June 14. That is so late, the Republican Party decided to use a caucus in D.C. instead. January 4, 2016 was the deadline for Republicans to qualify for the caucus. They either had to pay a fee of $15,000; or they had to pay $7,500 and submit 150 signatures of registered Republicans.
Three candidates collected signatures: Jeb Bush, John Kasich, and Marco Rubio. Seven other candidates paid the larger fee and skipped the petition: Ben Carson, Chris Christie, Ted Cruz, Carly Fiorina, Rand Paul, Rick Santorum, and Donald Trump. Thanks to Michael Beckel for the news.
Huckabee and Gilmore missing. Gilmore has missed over half the states already
I would wager that Gilmore will drop out shortly after the Iowa caucus or the New Hampshire primary, Huckabee likely will as well.