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House Democrats will get the ball rolling again on impeachment at a meeting Tuesday morning, deciding Tuesday or Wednesday on which House lawmakers will serve as managers at the Senate impeachment trial of President Trump. Assuming the House sends its two impeachment articles to the Senate on Wednesday, Trump's trial will likely start next week, though the Senate hasn't yet agreed on rules for the trial.

Trump tweeted Sunday that an impeachment trial would give "credence" and "credibility" to the House's charges, so Senate Republicans should vote for "outright dismissal." Senate Majority Leader Mitch McConnell (R-Ky.) has "signed on to an outlier proposal" to dismiss the charges without a trial, "but he does not have enough support in the Republican-held chamber to actually do it," The Associated Press reports. Instead, he's facing the possibility that a handful of Republicans could side with the Democrats and open the door to witnesses and new evidence.

Sen. Susan Collins (R-Maine) disclosed Friday that she has been working with a "fairly small group" of GOP colleagues to ensure a "trial that will allow the opportunity for both the House and the president's counsel if they choose to do so." She did not name names, though Sen. Lisa Murkowski (R-Alaska) said she wants rules like those used in President Bill Clinton's trial, which did allow witnesses. If four GOP senators sided with all 47 Democrats, they could control which rules were adopted.

Senate Minority Leader Chuck Schumer (D-N.Y.) told Politico that support for procuring new documentary evidence is "even stronger than we thought, with large numbers of Republicans supporting it." Trump will almost certainly survive the trial — conviction takes support from two-thirds of senators — but Democrats will make the most of demanding a "fair trial" to put vulnerable Republicans like Collins on the spot, and Republicans will apply other pressures to peel off any vulnerable Democrats.