WASHINGTON—The House impeached President Trump in a momentous set of votes late Wednesday, making him the third president since America’s founding to face a Senate trial, and laying bare the deep partisan divisions on Capitol Hill and across the country.

Nearly all Democrats, led by House Speaker Nancy Pelosi (D., Calif.), supported abuse-of-power and obstruction-of-Congress charges against Mr. Trump in the wake of his pressing Ukraine to investigate former Vice President Joe Biden, a leading 2020 Democratic presidential candidate.

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