Trump Dominates Michigan G.O.P. Convention Amid Party Turmoil

Former President Donald J. Trump capped off a clean sweep of Republican delegates in Michigan on Saturday during a raucous convention, which further exposed a deep fissure in the state party that threatens to fester in one of the most important battleground states.

Mr. Trump, the Republican front-runner, amassed at least 90 percent of the vote in all but one of the state’s 13 congressional districts against former Gov. Nikki Haley of South Carolina, who was ambassador to the United Nations under Mr. Trump.

A simple majority was needed in each district to win its share of delegates at the caucus-style event, giving Mr. Trump 39, to go along with the 12 that he won in Michigan’s primary, which was held on Tuesday. Ms. Haley emerged from that contest with four delegates.

Mr. Trump’s dominance earlier in the week left little doubt about the outcome of the convention on Saturday at the Amway Grand Plaza in Grand Rapids, Mich.

But a protracted fight over the state party’s rightful leader spilled over into the proceedings, where an estimated 200 Republican stalwarts from about 20 of Michigan’s 83 counties were denied credentials. Two other groups boycotted the event and held breakaway conventions, one more than 100 miles to the north in Houghton Lake, Mich., and another more than 50 miles southeast in Battle Creek, Mich.