There was his audacious pitch, as a freshman lawmaker, to Mr. Trump: Run for governor of New York, he told Mr. Trump in 2013, and the path to the White House would be clear. (“Springboards to the Presidency,” Mr. Nojay’s four-page memo was called.)

Image Assemblyman Bill Nojay at a rally in 2013. Credit... Mike Groll/Associated Press

Three years later, he was a co-chairman of Mr. Trump’s New York campaign committee.

There was his penchant for speaking up for upstate concerns, using his radio show to denounce state leaders in Albany — Democrats and establishment Republicans — for what he called their indifference. Among his signature issues: railing against the SAFE Act, the New York gun-control legislation passed in 2013.

“I’m not on the governor’s Christmas card list, and you know something? That’s something I wear as a badge of honor,” he said on Thursday, in one of his final radio interviews. “Because I think that when you forcefully and strongly advocate for your district and you make that mark, even people that disagree with you respect your views.”

The force of Mr. Nojay’s advocacy was not lost on anyone in the Legislature: “You knew exactly where he stood,” said Brian Kolb, the Assembly minority leader. “He ruffled feathers because he spoke it as he saw it.”

And there were his far-flung business and nation-building ventures. In Afghanistan, he was an election monitor with the International Republican Institute. In Odessa, Ukraine, he consulted on an election between pro-Western and pro-Russian candidates. In Iran, he held the title “director and secretary/treasurer of the Foundation for Democracy,” according to his Assembly biography.

In Cambodia, which he said he had visited for various reasons since the 1980s, he started an agricultural marketing business with three partners, including Sichan Siv, the Cambodian-American former United States ambassador to the United Nations. The Akra Group, as it was called, solicited a $1 million investment from a wealthy Phnom Penh dentist around the end of 2012, said her American lawyer, Robert A. Simon. By 2014, Mr. Simon said, Akra showed no signs of marketing rice or of returning the $1 million, and his client, Dr. Lykuong Eng, filed a fraud complaint in Cambodia.