ULAANBAATAR, Mongolia — A populist business tycoon and former judo star is set to win Mongolia’s presidency, unseating the country’s ruling party candidate in a runoff election.

With most polling stations counted, preliminary results Saturday showed Khaltmaa Battulga of the Democratic Party ahead with 50.6 percent of the vote. The ruling Mongolian People’s Party candidate, Miyeegombo Enkhbold, had secured only 41.2 percent.

Mr. Battulga campaigned on a “Mongolia First” platform, appropriating the catch phrase of President Trump. Mr. Battulga promised to be “a patriotic president,” seeking “equal cooperation” with neighbors like China, which he has criticized in the past.

Mr. Battulga told The Associated Press late Friday that under his leadership, foreign investment and technology would be welcomed in Mongolia — but that he would fight to get Mongolians greater benefit from that investment.