The National Republican Congressional Committee (NRCC) has expanded its list of vulnerable members who it will focus its incumbent retention program on.

The NRCC added 15 members to its Patriot program Wednesday, and they join the 10 members who were originally put on the list.

The new members are Reps. Mike Rogers (Ala.), Mary Bono Mack (Calif.), Bill Posey (Fla.), Tom Rooney (Fla.), Mario Diaz-Balart (Fla.), Lynn Jenkins (Kan.), John FlemingJohn FlemingCoast Guard suspends search for missing Ohio plane Freedom Caucus member to bring up bill on impeaching IRS chief GOP seeks to make it 52 MORE (La.), Bill Cassidy (La.), Michele BachmannMichele BachmannBachmann: Muslim immigrants trying to undermine Western civilization Religious leaders pray over Trump in Oval Office 'Real Housewives' producer 'begging' Conway to join cast MORE (Minn.), Blaine Luetkemeyer (Mo.), Lee Terry (Neb.), Scott GarrettScott GarrettConservative groups urge Trump to stick with Ex-Im Bank nominee Can the Washington swamp defeat Trump's nominee to run the Export-Import Bank? Overnight Finance: House votes to repeal arbitration rule | Yellen, Cohn on Trump's list for Fed chief | House passes Russia sanctions deal | GOP centrists push back on border wall funding MORE (N.J.), Dean HellerDean HellerWhy 'cherry-picking' is the solution to our nation’s flood insurance disaster Club for Growth endorses Nicholson in Wisconsin GOP primary Sen. Heller reveals: I voted for Trump MORE (Nev.), Charlie Dent (Pa.) and Cynthia LummisCynthia LummisFemale lawmakers flee House for higher office, retirement Despite a battle won, 'War on Coal' far from over Dems on offense in gubernatorial races MORE (Wyo.).

Posey, Rooney, Jenkins, Fleming, Cassidy, Luetkemeyer and Lummis are all freshman. The others were targeted by Democrats in 2008, with mixed results.

There are a few curious absences from the list so far.

One is Rep. Mike Castle (R-Del.). Several of the new Patriots had opponents raise big money against them in the second quarter, and Castle did too. Take it as a sign that the party believes there's little chance he will be seeking reelection.

Another is Rep. Bill Young (R-Fla.). Young comes from a tough district and has a solid opponent, yet seemingly less vulnerable members with no opponents are still being added to the list before him. Could be a sign of retirement.