Read Live Impeachment Trial Updates As Senate Votes On Witnesses

The impeachment trial of President Donald Trump continues Friday as senators vote on a motion to hear witnesses ― and if that motion fails, likely setting up votes to acquit Trump of the two charges against him.

The swift acquittal promised by Senate Majority Leader Mitch McConnell (R-Ky.) at the trial’s outset became much more likely late Thursday, when Sen. Lamar Alexander (R-Tenn.), a key swing vote, indicated he’d vote against calling witnesses.

GOP Sens. Mitt Romney of Utah and Susan Collins of Maine have said they intend to join Democrats in voting for the trial to continue with witnesses. Alexander’s decision likely leaves only Sen. Lisa Murkowski of Alaska as the one other only Republican who would favor the witness issue; her latest comments have been that still “processing” the arguments.

Should the motion to call witnesses result in a 50-50 tie, presiding officer Chief Justice John Roberts could cast a tie-breaking vote, though he isn’t obligated to. If he doesn’t, the motion fails. If he does so in favor of witnesses, Republicans can then call for a vote to overrule him.

The House managers of the impeachment case, led by Intelligence Committee Chairman Adam Schiff (D-Calif.), have been pushing for the Senate to subpoena Trump’s former national security adviser John Bolton. His forthcoming book reportedly confirms that the president withheld aid to Ukraine in an effort to smear political rival Joe Biden ― the crux of the impeachment case.

Acting White House chief of staff Mick Mulvaney would also make an informative witness, given his involvement in the scheme to withhold military aid to Ukraine and admission of a quid pro quo.

Read live coverage of Friday’s portion of the impeachment trial below:

Love HuffPost? Become a founding member of HuffPost Plus today.

This article originally appeared on HuffPost.