House Speaker Nancy Pelosi arrives for House Democratic Caucus meeting on Tuesday, Dec. 17, 2019, before a scheduled House Rules Committee hearing on the articles of impeachment against President Donald Trump on Capitol Hill in Washington. Photo: AP Photo/Patrick Semansky.

WASHINGTON – Democrats and Republicans were set to grapple on Tuesday over the rules of engagement for a historic vote set for Wednesday in the U.S. House of Representatives, where President Donald Trump is likely to become the third U.S. president to be impeached.

The Republican president remained in attack mode a day before his expected impeachment in the Democratic-led House, referring to the process in a Twitter post as “this whole Democrat Scam” and calling himself “your all time favorite President.”

“Don’t worry, I have done nothing wrong. Actually, they have!” Trump wrote.

In what is expected to be a marathon meeting, the House Rules Committee will decide how much time to set aside for debate on Wednesday before lawmakers vote on two articles of impeachment charging Trump with abuse of power and obstruction of Congress over his dealings with Ukraine.

Representative Jerry Nadler – the Democratic chairman of the House Judiciary Committee, which approved the articles of impeachment last week – will miss the Rules Committee meeting because of a family emergency, and Representative Jamie Raskin will represent the Democrats in his place, a congressional aide said. Nadler is expected to be back at the Capitol on Wednesday.