WASHINGTON – Andrew McCabe, the FBI’s deputy director who has been the target of GOP critics for more than a year, plans to retire in a few months when he becomes fully eligible for pension benefits, according to people familiar with the matter.

McCabe spent hours in Congress this past week, facing questions behind closed doors from members of three committees. Republicans said they were dissatisfied with his answers; Democrats called it a partisan hounding.

McCabe, 49, holds a unique position in the firestorm surrounding the FBI. He was former Director James Comey’s right-hand man, a position that involved him in most of the FBI’s actions that vexed President Donald Trump and in the investigation of ­Hillary Clinton’s use of a private e-mail server while secretary of state.

McCabe won’t become eligible for his full pension until early March. People close to him say he plans to retire as soon as he hits that mark. “He’s got about 90 days, and some of that will be holiday time.” one said.

McCabe’s plans drew a response Saturday from Trump on Twitter, calling the move “racing the clock to retire with full benefits.”

When Trump fired Comey in May, McCabe stayed to run the agency until a new director was in place and took the political heat for decisions made by his former boss.

“Andy’s in a difficult position now … because of the hyperpartisan political environment,” said John Pistole, who held the FBI’s No. 2 job for six years under former Director Robert Mueller. Mueller now serves as special counsel, running the investigation into whether any Trump associates conspired with Russian agents to interfere with the 2016 election.

Pistole said McCabe “is weathering the storm.”

“It’s disappointing,” he added, “to see how the criticism of the FBI is being used to try to undermine the credibility of the Mueller investigation. I think they’ve figured out they can’t undermine Bob’s integrity, so they’re just going to go after whoever they can dig up any dirt on.”

Within the agency, there is praise — but also some criticism — for how McCabe has handled his role. Still, he has become a lightning rod in the political storms buffeting the bureau. Conservatives have called for heads to roll at the FBI, and McCabe is atop the lists of many. But current and former FBI officials said it would be dangerous to appease those demands.

“It would send a terrible message to move him now, but it’s also a terrible situation he’s in,” said one official.

Last week, the FBI’s top lawyer, James Baker, told colleagues that he was being reassigned, according to people familiar with the matter.

The pressure on McCabe has only intensified. He got an eight-hour grilling from the House Intelligence Committee on Tuesday and returned to Congress on Thursday to face more than nine hours of questions from the House Judiciary and Oversight committees.

Other senior FBI officials, including those who worked closely with McCabe and Comey, are expected to face similar questioning from ­Congress next year.

Republicans are focusing in particular on the FBI’s relationship with the author of a dossier containing allegations against Trump. The bureau offered to pay the author of that document after the election to keep pursuing leads and information, but the agreement was never finalized, the Post reported earlier this year.