The pool of likely Republican appointees to the new House select committee on Benghazi is taking shape, with Speaker John Boehner, R-Ohio, set to reveal his picks later this week after the panel has been formally approved by a vote of the full chamber.

The lobbying by Republicans to win an appointment to the select committee has been intense, according to GOP members and other knowledgeable sources. But slots are limited and a House Republican leadership aide indicated that Boehner is narrowing the field to members who bring knowledge and expertise in the area of fact-finding and the events surrounding the Sept. 11, 2012, terrorist attack on the U.S. consulate in Benghazi, Libya, that left four Americans dead, including Ambassador Christopher Stevens.

"The most important thing — the overriding goal is to put together a group that will get to the truth for the American people," the leadership aide told the Washington Examiner on Tuesday.

Boehner is consulting senior members of his leadership team to get their input, as well as Rep. Trey Gowdy, R-S.C., the former federal prosecutor he named as select committee chairman. Whether House Democrats choose to participate also would affect which Republicans are selected.

Boehner’s decision on whom to appoint won’t be free from all political concerns. For instance, the speaker is likely to appoint at least one woman to the panel. On that front, his choices could include Rep. Ann Wagner, R-Mo., who previously served as the U.S. ambassador to Luxembourg. But there are multiple female House Republicans who fit Boehner’s criteria for an appointment, and all are probably receiving at least some consideration.

Overall, the candidates with a high probability of being tapped probably have been involved in the House Republicans' current inquiry into Benghazi as a member of the one of the five committees of jurisdiction that until now had been jointly investigating the deadly 2012 attack. Those committees include Armed Services, Foreign Affairs, Intelligence, Judiciary, and Oversight and Government Reform.

However, the chairmen of the five committees have a low probability of being selected, partly to avoid internal power struggles or the diminishment of Gowdy’s authority. Also unlikely to get the call are members who are retiring, just in case the select committee’s work runs into next year.

Those with a higher chance include the Republican members who have been serving on an informal committee, headed by Rep. Lynn Westmoreland of Georgia, that has been meeting for months to review the existing, five-committee investigation and look for ways to improve its performance.

They include Westmoreland and Rep. Devin Nunes of California, who serve on Intelligence; Rep. Jason Chaffetz of Utah, who serves on Oversight and Government Reform; Reps. Mike Conaway of Texas and Joe Heck of Nevada, who serve on Intelligence and Armed Services; and Rep. Adam Kinzinger of Illinois.

Rep. Mike Pompeo, R-Kan., a military veteran who serves on the Intelligence Committee, also is a possible candidate to receive an appointment to the select committee, sources said. Pompeo did not serve on the ad-hoc committee chaired by Westmoreland.