(Reuters) – The Democratic-led U.S. House of Representatives is expected to vote on Wednesday to send formal impeachment charges against President Donald Trump to the Senate, where Majority Leader Mitch McConnell has said he would help acquit his fellow Republican at a trial.

Here is what can be expected in the coming days and weeks:

Jan. 15

The House will vote to formally transmit the charges against Trump to the Senate, according to House Speaker Nancy Pelosi. Democratic lawmakers, who represent the House majority, voted along party lines on Dec. 18 to impeach Trump over his dealings with Ukraine.

The resolution would also appoint a number of House Democrats as “managers,” who would prosecute Trump in the Senate on charges that he abused his power by pressuring Ukraine to investigate former Vice President Joe Biden, a leading Democratic presidential contender for 2020, and that Trump obstructed efforts by Congress to uncover any misconduct.

Pelosi had delayed sending the charges to the Senate in an unsuccessful effort to get McConnell to agree to allow new witness testimony that could be damaging to Trump.

Jan. 16

A Wednesday vote would lead the Senate to take up impeachment on Thursday. The Senate will likely take several days to get through formalities before the trial begins in earnest.

The Senate would initially receive notification from the House that managers have been appointed and then adopt a resolution telling the House when it is ready to receive the managers to present the charges, known formally as articles of impeachment.

The House managers would then physically bring the articles of impeachment into the well of the Senate and present them. The Senate would inform the House when it is ready for the trial and organize for the proceedings.

U.S. Chief Justice John Roberts would be sworn in to preside over the trial. Senators would be sworn in as jurors.

Week of Jan. 20

House managers would present their case against Trump, and the president’s legal team would respond, with senators sitting as jurors. McConnell has said the Senate will sit in session six days a week, taking only Sundays off.

Senators would then be given time to submit questions to each side.

Senators could also vote on whether to dismiss the charges against Trump.

McConnell has said that, once the charges are formally submitted to the Senate, he will back a resolution that would set initial rules for the trial but postpone a decision on whether to hear from witnesses.

McConnell has not yet published a draft of the resolution but he said it would be “very similar” to one adopted in January 1999 during the impeachment of Democratic former President Bill Clinton.

That resolution set deadlines for the prosecution and defense to submit “trial briefs” that laid out their cases in writing. The resolution also allocated 24 hours for representatives of each side to make oral arguments and set aside 16 hours for senators to ask them questions.

The Clinton resolution referenced by McConnell did not resolve whether witnesses would be called. A follow-up resolution allowing for three witnesses to testify in videotaped depositions passed later along a party-line vote.

Late January to early February

Democrats will push to hear from witnesses during the trial. If McConnell’s resolution on initial trial rules is adopted, as expected, senators would likely vote after the trial has started on whether to introduce witness testimony sought by the Democrats. Republicans could seek to call witnesses of their own as well.

The Senate now has 53 Republicans, 45 Democrats and two independents who usually vote with the Democrats. That means four Republicans would need to cross party lines and join Democrats in requesting witness testimony.

The trial could continue into February, when Iowa and New Hampshire hold the first nominating contests for the 2020 presidential election. That could pose logistical problems for the four senators seeking the Democratic nomination: Bernie Sanders, Elizabeth Warren, Amy Klobuchar and Michael Bennet.

(Reporting by David Morgan and Jan Wolfe; editing by Andy Sullivan and Grant McCool)