Here is the 2016 Republican Primary Debate Schedule. The first one will be on August 6, 2015, at 9 p.m. EDT in Cleveland, OH, airing on Fox News Channel.
The rules of participation: “the Top 10 candidates in an average of 5 national polls will be included.”
I looked at the graphic above from the Washington Post on July 16, and the percentages were these: Jeb Bush: 17; Donald Trump: 10.8; Scott Walker: 9.3; Marco Rubio: 7.8; Ben Carson: 7.6; Rand Paul and Mike Huckabee tied at 6.5; Ted Cruz: 5.1; Rick Perry and Chris Christie tied at 2.9.
I looked again on July 17, and the numbers changed radically: Jeb Bush: 15.4; Donald Trump: 14.2; Scott Walker: 8.9; Ben Carson: 7.6; Rand Paul: 6.5; Marco Rubio: 6.4; Mike Huckabee: 5.7; Ted Cruz: 5.1; Chris Christie: 2.7; and Rick Santorum, who had been an also-ran at 2.2. Rick Perry slipped off the podium at 2.1, along with John Kasich: 1.5; Bobby Jindal: 1.4; Carly Fiorina: 1.3; Lindsay Graham: 0.7; George Pataki: 0.5.
I don’t know what the cutoff date for selecting the candidates, but Christie, Perry, and Santorum seem to be battling for the last two slots.
(Hat tip to Arthur@AmeriNZ.)