But the public is weary of Mr. Trump’s flirtation “with a dictator who had his uncle executed, killed a South Korean citizen and blew away an inter-Korean liaison office,” said Cheon Seong-whun, former head of the Korea Institute for National Unification, a government-funded Seoul think tank. “Trump has shocked South Koreans repeatedly, putting them on a constant alert,” he said. Polls show they favor Mr. Biden by nearly four to one.

Mr. Trump has continued to antagonize other parts of the globe in the final weeks of the campaign, speculating that Egypt might “end up blowing up” a contentious $4.6 billion hydroelectric dam on the Nile that Ethiopia is building. The remarks worsened one of the most delicate disputes in Africa and further polarized opinions about the American election in both countries.

Many Ethiopians are backing Mr. Biden by default, analysts said. But Yasser Rezk, an Egyptian journalist close to President Abdel Fattah el-Sisi — whom Mr. Trump once called “my favorite dictator” — said Egyptians are rooting hard for a Trump victory. “Unfortunately, we don’t have a vote,” he said.

In the Middle East, where Mr. Trump’s foreign policy has had the biggest impact, the biggest impact of a Democratic victory could be to leave the autocratic leaders of Egypt, Saudi Arabia and Turkey with few friends in Washington, said Hisham Melhem, a columnist for the Lebanese newspaper Annahar Al Arabi.

That could prod Saudi Arabia, which Mr. Biden has called a “pariah state,” into offering to normalize ties with Israel, if only to blunt calls to re-evaluate the Saudi-American relationship, he said.

Conversely, a Trump victory offers Israel no guarantees. A second-term President Trump, unfettered of his need to please pro-Israel evangelical voters, might rush into an overly forgiving new deal with Iran, many Israelis fret.