President-elect Donald Trump has begun filling out his administration with names well-known in Congress and Republican circles.

But many have been dogged by controversy and could find their nominations in the Senate held up by Democrats.



Sen. Jeff Sessions for attorney general

Trump has tapped Sessions as his attorney general pick, the president-elect's transition team confirmed Friday.

In February, the Alabama senator became the first sitting senator to endorse Trump during his campaign. His name was also floated as a possible running mate for Trump.



Sessions is chairman of the Senate Subcommittee on Immigration, and served as an adviser on Trump's immigration policy plan during his campaign.



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When he first endorsed Trump, Sessions praised the then-GOP contender as someone who would finally fix illegal immigration.

As a current member of the Senate, it's unlikely that Sessions' Republican colleagues will try to block his nomination. But Democrats and liberal groups are sure to focus on Sessions' controversial past.



In the 1980s, Sessions was considered for a Ronald Reagan-appointed federal district judgeship in Alabama, but was blocked by the Senate after a black former deputy, Thomas Figures, accused him of making racially insensitive statements. Figures said that Sessions had once warned him to be careful about what he said to "white folks."



Ret. Lt. Gen. Mike Flynn for national security adviser



Flynn — a controversial figure who has been known to eschew "political correctness" — is a Trump loyalist who stayed by the candidate's side even as other national security experts sharply criticized him during the campaign.

NBC News reported in July that Trump's team vetted Flynn as a possible vice presidential running mate.



But Trump has offered Flynn the job as a national security adviser.



The special assistant to the president for national security affairs coordinates the synthesis and presentation of the information generated by the vast U.S. national security apparatus — the State Department, the Defense Department, the CIA, the National Security Agency and a host of other intelligence agencies. The national security adviser serves as the president's top day-to-day counselor on foreign and military affairs.

Flynn's appointment doesn't require confirmation by the Senate.



Flynn, 57, a 33-year veteran of the Army, was director of the Defense Intelligence Agency from 2012 to 2014.



As speculation about Flynn's appointment spread Thursday night, critics highlighted some of his controversial past statements. In February, Flynn said on Twitter that "fear of Muslims is rational."



Fear of Muslims is RATIONAL: please forward this to others: the truth fears no questions... http://youtu.be/tJnW8HRHLLw

Rep. Mike Pompeo for CIA director

Kansas Rep. Mike Pompeo has accepted Trump's offer to be CIA chief in his new administration, the transition team confirmed.

Pompeo, a 52-year-old Wichita Republican, was elected to Congress in 2010 as part of the wave endorsed by the tea party and backed by Republican mega-donors Charles and David Koch. He is a former Army officer and Harvard graduate who serves on the House Intelligence Committee.



He was also a vocal member of the House Select Benghazi Committee, a special panel convened to probe the Sept. 11, 2012, attack in Libya that left four Americans dead, including U.S. Ambassador Chris Stevens.

Pompeo and Rep. Jim Jordan, R-Ohio, released their own report criticizing former Secretary of State Hillary Clinton in her role at the time, saying she misled Americans about how the attack evolved because President Barack Obama was up for re-election.



Pompeo has gotten backlash from past remarks about Muslims after saying on the House floor in 2013 that Islamic leaders failed to widely condemn the Boston marathon bombing — and appeared "complicit" in the attack.



"Instead of responding, silence has made these Islamic leaders across America potentially complicit in these acts and more importantly still, in those that may well follow," Pompeo said.



Trump has not publicly announced the pick.