Of the 17 Republican presidential candidates who participated in the first national TV debates of the campaign Thursday on Fox News, 16 — including Gov. Bobby Jindal — have been invited to join the next round Sept. 16 on CNN, the network announced Tuesday.

And the odd man out, former Virginia Gov. Jim Gilmore, still could make the field for the two-tiered debates, which will be broadcast live from the Air Force One Pavilion at the Ronald Reagan Presidential Library in Simi Valley, California.

But the more closely watched outcome of CNN’s sorting of the candidates is likely to be which 10 make the headline debate and which are relegated to the undercard.

Reagan’s widow, former first lady Nancy Reagan, officially extended the invitations.

Gilmore is the last of the candidates who has held statewide office or otherwise enjoys a national reputation to join the race, announcing his intentions July 30. He has not yet met the requirement of registering at least 1 percent support in three national polls recognized by CNN and released between July 16 and Sept. 10.

Gilmore did score 1 percent in a CBS News poll conducted July 29 to Aug. 2. In the more than one dozen other polls released since July 16 and available on the Real Clear Politics website, Gilmore either scores below 1 percent or was not included in the poll.

Other criteria set by CNN for participation in the Sept. 16 debates include: meeting the constitutional requirements for serving as president; filing a statement of candidacy with the Federal Election Commission by Aug. 26; having at least one paid campaign aide working in two of the four “early voting states” designated by the Republican National Committee (Iowa, Nevada, New Hampshire and South Carolina) no later than Aug. 26; and visiting two of those four states by Aug. 26.

The invitations to Jindal and the 15 other candidates were expected, based on the criteria.

CNN will use average results of national surveys released in the July 26 to Sept. 10 window to rank the top 10 candidates, who will participate in the top-billed debate. The also-rans will again debate on their own.

Fox News divided the debate field into two tiers: A prime-time lineup of the candidates ranking in the top 10 on average in the most recent national polls leading up the debates, and a late-afternoon grouping of the seven candidates, including Jindal and Gilmore, who did not make the first cut. The prime-time debate attracted 24 million viewers, a record for the network, while the earlier debate drew one-fourth that number.

But in contrast to Fox, which broadcast the live debates several hours apart, CNN will conduct them back-to-back. The network is still working on the details of the scheduling, a spokeswoman said. CNN “State of the Union” anchor Jake Tapper will serve as moderator for both debates.

Jindal was ranked 13th by Fox heading into its debates. He was tied for 13th Tuesday in the RCP average of four recent national polls.