Trump Thinks Corey Lewandowski Would Be a ‘Fantastic’ Senator From New Hampshire

President Trump on Thursday all but endorsed his former campaign manager, Corey Lewandowski, for a potential Senate run from New Hampshire, saying he would be “hard to beat” if he ran and a “great senator” if he won.

Mr. Trump made the remarks in an interview with the New Hampshire radio host Jack Heath, amid reports that Mr. Lewandowski is seriously considering a campaign in his home state to become the Republican challenger to the Democratic incumbent, Senator Jeanne Shaheen.

Mr. Lewandowski is expected to ride in the presidential motorcade Thursday night with Mr. Trump from the airport in Manchester, N.H., to a re-election campaign rally that Mr. Trump will hold nearby.

For days, questions have swirled about whether Mr. Trump will endorse Mr. Lewandowski, who has not yet declared his candidacy, at the rally. An announcement from Mr. Lewandowski about the Senate race is not yet imminent, according to a person working with him.

Still, Mr. Trump appeared eager to elevate Mr. Lewandowski. When Mr. Heath asked if Mr. Lewandowski would have the president’s support if he ran, Mr. Trump stopped short of a full endorsement, saying that Mr. Lewandowski hadn’t made up his mind about joining the race. But he went on to say, “I have to tell you, I think he’d be fantastic.”

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“He’s got great energy, he’s terrific on television,” Mr. Trump said. “I like everything about him.”

He added, “If he ran, I think he’d be number one. I think he’d be hard to beat in New Hampshire.”

Mr. Trump fired Mr. Lewandowski at the urging of his children in June 2016, but the president has retained a fondness for him and speaks with him often. Before his ouster, Mr. Lewandowski helped Mr. Trump notch his first primary victory, in New Hampshire, a win that helped vault him to the nomination. Mr. Lewandowski would hope to run on the same outsider energy that Mr. Trump channeled that year.

Just how formidable Mr. Lewandowski would be is a source of disagreement among political professionals, most of whom predict an ugly Republican primary race and general election in New Hampshire.

His opponents would be almost certain to raise questions about his business activities since Mr. Trump went into office. Mr. Lewandowski co-wrote two books about Mr. Trump with David Bossie, the head of the conservative group Citizens United.

But he has also been an adviser to companies that have interests with the government, and he would be required to file financial disclosure forms that would reveal the extent of those business arrangements.

Mr. Lewandowski has previously said he is not a lobbyist, and that he has never called government officials on behalf of a client.

The Republican Senate primary in New Hampshire already has several declared candidates, including the retired Brig. Gen. Donald C. Bolduc and Bill O’Brien, the former state house speaker. After Mr. Bossie released a private poll he had commissioned from a pollster working with Mr. Trump’s campaign that showed Mr. Lewandowski leading in a theoretical Republican primary, aides to Mr. Bolduc released their own internal survey showing Mr. Bolduc ahead.