On the eve of the vote, Mr Trump said he was being subjected to an "attempted coup" and a witch trial.
Mr Trump is accused of attempting to force Ukraine into investigating a main 2020 reelection rival, Joe Biden. That will send the case to the Senate, where a trial of Mr Trump is expected to open in January, and his acquittal is equally expected, given the Republicans' control there. While the debate occurs, Mr Trump will fly to Battle Creek, a city in the swing state of Michigan to host a rally this evening.
"My military service taught me to put our country, not politics, first, and my time as a federal prosecutor taught me about the importance of the rule of law and of justice," declared Mikie Sherrill, a first-term representative from a Trump-leaning district in New Jersey."I know some people will be angry at my decision, but I was elected to do what is right, not politically safe," said Anthony Brindisi, another first-term Democrat, from a conservative New York constituency.