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Donald Trump and his legal team worked into the night after a bombshell New York Times article quoted a former White House aid who heard Trump say he would withhold aid to the Ukraine.

At least 2 Republican senators appear to be reconsidering their vote to call witnesses during the Senate impeachment trial.

According to the New York Times article, former National Security Advisor John Bolton confirmed there was a quid pro quo by Trump. Bolton said he heard Trump say he would refuse to releases hundreds of millions of dollars in aid to the Ukraine unless they helped investigate corruption by former VP Joe Biden and his son Hunter Biden.

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But Trump accused Bolton (pictured right) of outright lies. Trump sent out a series of late-night tweets insisting he never had that conversation with Bolton or adviser Rudy Giuliani. The president said Bolton made up the allegations to sell books.

House Democrats declined to call Bolton to testify during the House impeachment hearings in December. But House impeachment managers insist Republican senators should call Bolton to hear his crucial testimony.

According to an unpublished manuscript of Bolton's new book, Trump said he would freeze military aid to Ukraine unless it helped investigate the Bidens.

Democrats need at least 4 senators to vote with them to call new witnesses to testify.

Two GOP senators, including Maine Senator Susan Collins, have indicated they will reconsider their decisions not to call witnesses.

The Senate trial was scheduled to wrap up on Friday, but the shocking new developments may extend the trial for weeks.