U.S. senators are bracing for a rancorous debate over the trial’s ground rules, which will determine how Democrats prosecute Mr. Trump on charges of abuse of power and obstruction of Congress linked to his Ukraine pressure campaign.

Senator Mitch McConnell, the chamber’s top Republican, angered Democrats on Monday by unveiling trial rules that would limit each side’s arguments to 24 hours over two days, and require a separate vote to admit evidence unearthed in the fall by the House of Representatives.

Analysis: Mr. Trump’s lawyers have not contested the basic facts of the case, and scholars say their central argument — that the impeachment charges are invalid because the president has not been accused of committing an ordinary crime — defies a long-established legal consensus.

Go deeper: The trial will include some of the same faces that animated President Bill Clinton’s impeachment trial 21 years ago. But Mr. Clinton did not command his own party the way Mr. Trump does now.

Related: The business and political elites who gather each year at Davos appear to be warming to Mr. Trump, even if some may roll their eyes behind his back, writes our DealBook columnist, Andrew Ross Sorkin. (One reason? He may be in office for another four years.)