U.S. President Donald Trump flashes a thumbs-up as he arrives at the World Economic Forum in Davos, Switzerland, Wednesday, Jan. 22, 2020. The 50th annual meeting of the forum is taking place in Davos from Jan. 21 until Jan. 24, 2020. (AP Photo/Michael Probst)

WASHINGTON (AP) — The U.S. Senate plunged into President Donald Trump’s impeachment trial with Republicans abruptly abandoning plans to cram opening arguments into two days but solidly rejecting Democratic demands for more witnesses to expose what they deem Trump’s “trifecta” of offenses.

The daylong session started Tuesday with the setback for Republican Senate leader Mitch McConnell and the president’s legal team, but it ended near 2 a.m. today with Republicans easily approving the rest of the trial rules largely on their terms.

The result is Trump’s historic trial, unfolding amid a watchful public in an election year.

“We have a great case,” Trump said as he began his second day at a global economic forum in Davos, Switzerland. He said he thought his legal time was doing a “very good job.”

The trial is now on a fast-track with almost no signs of Republican resistance to the actions that led to his impeachment.

“It’s about time we bring this power trip in for a landing,” said White House counsel Pat Cipollone, the president’s lead lawyer, lashing out at the House Democrats prosecuting the case.

“It’s a farce,” he said about the impeachment proceeding, “and it should end.”

Chief Justice John Roberts gaveled open the session, with House prosecutors on one side, Trump’s team on the other, in the well of the Senate, as senators sat silently at their desks, under oath to do “impartial justice.” No cellphones or other electronics were allowed.

As the day stretched deep into the night, lawyerly arguments gave way to more pointedly political ones. Tempers flared and senators paced the chamber. Democrats pursued what may be their only chance to force senators to vote on hearing new testimony.

After one particularly bitter post-midnight exchange, Roberts intervened, taking the rare step of admonishing both the Democratic House managers prosecuting the case and the White House counsel to “remember where they are.”

“I think it is appropriate at this point for me to admonish both the House managers and the president’s counsel in equal terms to remember that they are addressing the world’s greatest deliberative body,” the usually reserved Roberts said. He told them that description of the Senate stemmed from a 1905 trial when a senator objected to the word “pettifogging,” because members should “avoid speaking in a manner and using language that is not conducive to civil discourse.”

Over and over, Republicans turned back Democratic amendments to subpoena documents from the White House, State Department, Defense Department and budget office. By the same 53-47 party-line, they turned away witnesses with front-row seats to Trump’s actions including acting White House chief of staff Mick Mulvaney.