Top White House officials and sources close to White House counsel Don McGahn tell Axios that McGahn will step down this fall — after Brett Kavanaugh is confirmed to the Supreme Court, or after the midterms. The president later confirmed Axios' reporting in a tweet.

The big picture: This potentially puts a successor in charge of fielding a blizzard of requests or subpoenas for documents and testimony if Democrats win control of the House in the midterms. And if the White House winds up fighting special counsel Robert Mueller, an epic constitutional fight could lie ahead.

We're told that Trump has not formalized a successor.

Trump has not formalized a successor. But McGahn has told a confidant he would like his successor to be Emmet Flood, a Clinton administration alumnus who joined the White House in May to deal with the Russia probe.

has told a confidant he would like his successor to be Emmet Flood, a Clinton administration alumnus who joined the White House in May to deal with the Russia probe. Flood also served for two years during George W. Bush’s second term as his top lawyer handling congressional investigators.

A source familiar with Flood's thinking said: “The reason he can represent both Bill Clinton and Donald Trump is because he thinks these investigators come and basically put a target on their backs, trying to overturn every aspect of their lives searching for a crime."

"He feels that is a judicial and constitutional hazard."

Three senior administration officials tell us they hope Flood is the pick:

He’s trusted and respected inside the White House.

and respected inside the White House. Most importantly, sources familiar with their interactions say Flood has — as well as any lawyer can — figured out how to talk to Trump.

sources familiar with their interactions say Flood has — as well as any lawyer can — figured out how to talk to Trump. The president focuses his attention when Flood talks to him: Trump reacts to the authority Flood carries as a heavyweight lawyer handling the topic that potentially poses an existential threat to the Trump presidency.

The timing for a McGahn departure is right for both sides, the officials say:

McGahn , whom some Trump allies fear coughed up too much information during his extensive cooperation with Mueller’s team, would leave on a high note, after the confirmation of Justice Neil Gorsuch, and the expected confirmation of Judge Brett Kavanaugh.

, whom some Trump allies fear coughed up too much information during his extensive cooperation with Mueller’s team, would leave on a high note, after the confirmation of Justice Neil Gorsuch, and the expected confirmation of Judge Brett Kavanaugh. McGahn ran point on Trump's record run of conservative judicial selections, which has endeared Trump not only to his base but also to Republicans skeptical of his presidency.

on Trump's record run of conservative judicial selections, which has endeared Trump not only to his base but also to Republicans skeptical of his presidency. In Flood, Trump would get a White House counsel with impeachment chops from the Clinton years, and little internal baggage.

Trump would get a White House counsel with impeachment chops from the Clinton years, and little internal baggage. McGahn has told a confidant that he doesn't expect to leave Trumpworld entirely after he leaves the White House. He privately said he expects to continue to be of assistance to the president through the re-election campaign.

Be smart: McGahn has had, at times, a strained relationship with the president.

A defender of McGahn's, who has been an uncomfortable bystander while the president has torn shreds off of McGahn, told Axios that McGahn did the best he could under very trying circumstances, and often had to bat back unreasonable and legally problematic requests.

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