Raymond Kethledge was working on his book about leadership and solitude in 2016 when the phone rang. It was the landline, because in the office of his northern Michigan barn, situated in a densely forested area overlooking Lake Huron, Kethledge had no cell service or Internet access.

It was his wife, said Kethledge, a judge on the U.S. Court of Appeals for the 6th Circuit, recalling the moment in an interview with the legal blog Above the Law. She was calling to say he had been mentioned on television as one of the handful of names then-presidential candidate Donald Trump released to reassure conservatives about the type of jurists he would nominate to the Supreme Court.

“That was how I heard the news,” Kethledge said in the interview last year. “It was distracting. I really had to get that chapter done in the short time I had up there. So I thanked my wife for letting me know, and went back to work.”

Two years later, the self-described introvert and outdoorsman finds himself again in the political spotlight — this time on the shortlist President Trump is considering to replace retiring Supreme Court Justice Anthony M. Kennedy.

Kethledge, 51, cuts an improbable figure for the capital at this fractious political moment. He praises the virtues of unplugging and is prone to calls for civility. Asked during his 2008 appeals court confirmation hearing if he had any legal problems in his past, he could only muster “a few speeding tickets a long time ago.”

The married father of two is described by those who know him as a quintessentially “Michigan guy” who fishes and is fond of hunting grouse (“or partridge, as we call them in Michigan,” he once remarked). Kethledge, who did not respond to an interview request, attended the University of Michigan for his undergraduate studies and law school, a contrast with others on the high court, which is awash in Ivy League diplomas.

“He does bring a kind of interesting diversity to the court,” said former senator Spencer Abraham (R-Mich.), who has known Kethledge since the judge worked as his judicial counsel in the 1990s.

“That is, the kind of background of somebody who wasn’t part of the Washington world or the Ivy League world, who went to state schools, who had more of a regular-guy-type background,” Abraham said.

While attention in recent days has focused largely on his better-known peers — federal appellate judges Brett M. Kavanaugh and Amy Coney Barrett — Kethledge is believed to be under consideration with them as a top contender to replace Kennedy, for whom he once clerked.

His rapid ascent in recent days has been marked with praise from supporters calling him “Gorsuch 2.0” — a reference to Justice Neil M. Gorsuch, another conservative former Kennedy clerk whom Trump nominated last year.

Hugh Hewitt, the conservative commentator and radio host, wrote an op-ed in The Washington Post on Monday urging Trump to pick Kethledge, describing him as an “originalist” like the late Justice Antonin Scalia and praising him as a judge with “an exemplary record on Second Amendment rights.”

Kethledge has faced criticism from liberals as well as some conservatives taking aim at his rulings and views on a host of issues, including immigration and reproductive rights.

Senate Minority Leader Charles E. Schumer (D-N.Y.) wrote on Twitter that Kethledge “has a history of opposing women’s reproductive freedom,” linking to an article citing his work with Abraham, an abortion opponent.

The liberal Alliance for Justice posted in a summary of Kethledge that he “fights for wealthy and powerful over the rights of all”; had issued rulings harmful to the environment, immigrants and voters; and, if nominated, “would threaten the rights of consumers, workers, and immigrants, as well as women’s reproductive rights and the rights of the accused.”

Kethledge also has earned the scorn of some conservatives who question his views on immigration. They point to one case in which he joined the majority to side with a Vietnamese immigrant who faced deportation after not disclosing a conviction for auto theft and cocaine possession when applying for citizenship.

The opinion concluded that the car theft did not fit the bill of a “crime of violence” and, therefore, was not an “aggravated felony” that warranted deporting him.

“The judges are supposed to decide the cases based on what’s before them,” said Jonathan H. Adler, a law professor at Case Western Reserve University. “His record generally shows that he takes these questions seriously, that he makes the effort not to insert his personal views into decisions. That’s generally what you want in a potential judicial nominee.”

One of Kethledge’s better-known opinions came in a case involving allegations that the Internal Revenue Service had mistreated conservative groups under President Barack Obama. Kethledge wrote that the government responded to the lawsuit with “continuous resistance.” He reacted not with a blistering rebuke but using the measured language for which he is known.

“The lawyers in the Department of Justice have a long and storied tradition of defending the nation’s interests and enforcing its laws — all of them, not just selective ones — in a manner worthy of the department’s name,” Kethledge wrote in his 2016 opinion. The government had not lived up to that, he continued, adding: “We expect that the IRS will do better going forward.”

In 2015, Kethledge joined in an opinion invoking “the fundamental right to possess a gun.”

This year, he broke from the majority in a case reviewing the actions of a Michigan sheriff’s deputy who used a stun gun and pepper spray, and hit a man in the head 15 to 20 times. The majority said the blows were gratuitous, but in his dissent, Kethledge said “each blow was necessary” because the man was “defiant throughout, refused to stay on the ground, and resisted being handcuffed.”

Last year, Kethledge published “Lead Yourself First,” a book he co-wrote with Michael S. Erwin, a friend and veteran of the wars in Iraq and Afghanistan who founded a nonprofit seeking to help other veterans.

The book argues that good leadership requires a measure of solitude, a rare commodity in these hyper-connected times.

“Society did not make a considered choice to surrender the bulk of its time for reflection in favor of time spent reading tweets or texts,” they wrote.

Kethledge described in the book how, while clerking for Kennedy, he “walked alone around the Capitol and the Supreme Court building when thinking through a case.” It is a practice he echoes now by writing opinions in his barn, which is outfitted with a wood-burning stove and a simple pine desk.

“Fortunately,” he told the blog, “my cellphone doesn’t work up there.”

Alice Crites and Amy Brittain contributed to this report.