But Trump and his campaign argue, despite a lack of evidence, that widespread mail-in voting will benefit Democrats and invite fraud. The Republican Party is spending tens of millions of dollars on a multifront legal battle.

“My biggest risk is that we don’t win lawsuits,” Trump said. “We have many lawsuits going all over. And if we don’t win those lawsuits, I think — I think it puts the election at risk.”

Trump was asked a two-part question during the interview: Would a substantial amount of mail-in voting — which is widely expected because of coronavirus — cause him to question the legitimacy of the election? And would he accept the results no matter what?

“Well, you can never answer the second question, right? Because Hillary kept talking about she’s going to accept, and they never accepted it. You know. She lost too. She lost good.” Clinton conceded the day after the 2016 election.

Trump struck a firmer note last week in an interview with Fox News, when he said he would leave office peacefully if he lost.

The president’s rare admission of concern about his political future comes at the most precarious moment of his presidency. Polls have shown the president trailing in an array of key states — some of which haven’t been lost by a Republican in decades — amid criticism of his handling of the coronavirus pandemic and his response to the protests against police brutality.

Now, with Republicans fighting to keep their Senate majority, lawmakers running in competitive races are having to decide whether to align themselves with the president or risk his wrath by creating daylight. Trump made clear those who choose the latter will pay a heavy price.

Joined by top aides, including his son-in-law Jared Kushner, Trump put Senate Republicans on notice: Running away from him would only trigger a revolt by his loyalists.

“If they don’t embrace, they’re going to lose, because, you know, I have a very hard base. I have the strongest base people have ever seen,” said Trump, who met with Senate Majority Leader Mitch McConnell last week to discuss the party’s prospects in key Senate races.

Trump is keenly aware of how he stacks up against other Republicans on the ballot this fall. At one point during the interview, White House Political Director Brian Jack handed the president a document showing how he had fared better in several primaries this spring than a handful of Republican senators he shared the ballot with in their home states. Included on the chart was North Carolina Sen. Thom Tillis, one of the most vulnerable Republican incumbents up for reelection this November. While Tillis received 78 percent in the state's March primary, Trump got 94 percent, it noted.

"Wow, that’s great in North Carolina, huh?" Trump remarked as he looked over the sheet.

Senate Republicans have largely remained in lockstep with the president, but there have been a few exceptions. Maine Sen. Susan Collins, one of the party’s most vulnerable lawmakers, has yet to say whether she backs Trump’s reelection and didn’t appear with him when he visited her home state last week. Michigan GOP Senate candidate John James recently told black community leaders that he disagreed with Trump on “plenty, plenty of issues.”

During the interview, Trump rattled off a list of senators who lost their seats after separating themselves from him. He recalled ending the political careers of Tennessee Republican Bob Corker (“So, anyway, I went after him,” he said. “No longer a senator.”) and Arizona Republican Jeff Flake (“He went from 54 percent to 3.”). Nevada Republican Dean Heller “went down” in the general election (“How did it work out for the great senator of Nevada? Not too good.”).

“We will, on occasion, have some senators that want to be cute,” he said. “And they don’t want to embrace their president.”

Much of the president’s focus, though, was on his own race. He portrayed Biden as a weaker candidate than Clinton. Clinton, Trump said, was “obviously smarter" than Biden. And after savaging Clinton for having "no stamina" in 2016, the president indicated he thought she had more energy than the 77-year-old Biden.

"I can tell you a lot about Hillary," Trump said. "She had a lot of energy and she was smart."

Even as coronavirus cases are rising in many places, the president insisted the virus is on the decline. He said it is “heading south" — "meaning leaving.” Days before his first major rally during the pandemic, Trump accused Biden’s campaign of using coronavirus as an excuse to shield him from public scrutiny, including questions from the media.

"We haven’t really seen the real Joe because they have him — they’re hiding him," Trump said. Biden and his campaign say he's acting responsibly and heeding the advice of public health experts.

Trump was clearly fixated on the forthcoming tell-all book by former national security adviser John Bolton. He described Bolton as a “whack job” and a “sick customer” and said that “everybody thought he was totally nuts.” He recalled having a conversation with Bolton in which the former adviser defended his outspoken support for the Iraq War.

“I said, ‘John, honestly, if you believe that now — I could understand maybe at the time — but if you believe that now, there’s something seriously wrong with you,’” Trump said.

As he was wrapping up the interview, Treasury Secretary Steven Mnuchin entered the Oval Office to summon Trump for a meeting with the governors of Nebraska and Oklahoma. Before they headed out, Trump looked over a critical review of the Bolton book and the two reveled in the drubbing. The president appeared very pleased.