Now that Ayers has ruled himself out—only willing to serve until spring—leaving some in the West Wing expressing shock and Trump claiming Mike Pence’s chief of staff never the first choice, according to The Hill, there’s the question of who might now be available. Four names are reported to be on the list, all of whom have varying degrees of controversy.

House Freedom Caucus Chairman Rep. Mark Meadows (R-N.C.) is generally a strong supporter of Trump. He was one of 18 House Republicans who nominated the president for the Nobel Peace Prize for previous attempts to negotiate with North Korea. Meadows also pushed to declassify the secret court application for permission to monitor former Trump campaign foreign policy adviser Carter Page, which led to Robert Mueller’s position as special counsel.

White House budget director Mick Mulvaney, who also served as the interim Consumer Financial Protection Bureau, told bankers about his time in Congress, “If you’re a lobbyist who never gave us money, I didn’t talk to you. If you’re a lobbyist who gave us money, I might talk to you.” He was also reportedly involved in a meeting and decision to halt relocation of FBI headquarters to keep the old site from being turned into a hotel that could compete with the Trump International.

U.S. Trade Representative Robert Lighthizer is considered a China hawk and has supported tariff escalation that has had a negative impact on multiple industries. And many have seen Acting Attorney General Matthew Whitaker compromised over on-the-record statements about the Russia investigations.

However, Trump does not need Senate confirmation for his chief of staff pick.