LAS VEGAS — Two strikingly divergent visions of Republican political strength played out over the weekend at a conference of Jewish conservatives, the first major gathering of G.O.P. leaders since the party’s sweeping success in Tuesday’s elections. There were displays of blustery confidence. And there were calls for caution and restraint as party leaders tried to process their drastic gains.

Looming over it all, and mostly addressed gingerly, was the uncertainty about whether Republicans could replicate their decisive gains with suburban voters, especially women, if former President Donald J. Trump remained the face of the party.

Although a majority of the speakers at the annual conference of the Republican Jewish Coalition were effusive with their praise of the former president and spent much of the two-day gathering citing his administration’s most conservative policy achievements, others warned that Republicans who continued to give cover to his baseless claims about fraud in the 2020 election were jeopardizing the party’s recent success.

The most notable Trump skeptic was former Gov. Chris Christie of New Jersey, who urged Republicans to promote a “plan for tomorrow, not a grievance about yesterday,” and said that the party would be making a grave mistake if it did not recommit itself to truth-telling.

“Winning campaigns are always the campaigns that look forward, not backwards,” Mr. Christie said, earning only a smattering of applause from the crowd. Noting the less-than-enthusiastic response, Mr. Christie implored the audience: “That deserves applause. Because if we don’t get it, we are going to lose.”

The 2020 election, Mr. Christie said, “is over.”

But that was not the message delivered by most other speakers — a group that included more than a half dozen of the current and former governors and senators who are considered possible presidential contenders and leaders-in-waiting whenever Mr. Trump recedes from the spotlight.

They offered much different interpretations of the results on Election Day last week, which delivered wins for Republicans in Democratic strongholds up and down the ballot — from Virginia, where they won the governor’s race for the first time since 2009, to Washington State, where a candidate running on a message of law and order prevailed in the contest for city attorney in Seattle. Republicans also picked up seats in municipal races across New York City and Long Island and came close to pulling off a colossal upset in the governor’s race in New Jersey.

“The trend is unmistakable,” said Representative Kevin McCarthy, the House Republican leader who hopes to lead his party back into the majority next year. “A Republican wave is underway.”

A year into the Biden administration, polling data, history and Tuesday’s results indicate the political climate has become highly unfavorable to Democrats, who have proved that they can beat Mr. Trump but have not convinced enough Americans that they can govern effectively.

The election results last week only boosted the optimism of Republicans who already believed they were likely to win the small number of seats they needed to win control of the House next year and were in a strong position to win a majority in the Senate as well.

That confidence was irrepressible at their gathering in Las Vegas this weekend, as Republicans predicted not only big gains in the 2022 midterm elections, but in 2024 as well.

Senator Ted Cruz of Texas said the results last week foreshadowed a victory in the House and the Senate. He also praised the “extraordinary courage” and “steel backbone” that Mr. Trump displayed as president.

Mr. Cruz giddily described the despondency he said he witnessed among his Democratic colleagues on Capitol Hill over the election last week and vowed that the 2022 midterms would bring about the day when “Nancy’s going to get on her broom” and “fly back to California.” That remark, referring to the first woman to hold the position of speaker of the House, Nancy Pelosi, drew a round of hearty laughter from the audience.

Speaking with reporters after his speech on Friday night, Mr. Cruz pointed to how suburban mothers were “coming home to the Republican Party” as a hopeful sign of the party’s fortunes. “I think there are a lot of people across this country, including some soccer moms in Virginia who may have voted for Joe Biden, and looked at this past year and were horrified.”

But he twice declined to say whether the G.O.P. could again expect similar results if Mr. Trump — who repelled suburban men and women in such high numbers in 2020 that it cost him several swing states — resumed his role as his party’s standard-bearer.

Still, like many other top Republicans who have offered their analysis of the country’s suddenly jolted political landscape, Mr. Cruz indicated that he believed the poor public perceptions of President Biden and the Democratic Party were enough to guarantee Republican success.

Gov. Ron DeSantis of Florida, who is frequently mentioned as a top contender for the Republican 2024 presidential nomination should Mr. Trump decide not to run, thundered against what he called a “Fauchian dystopia,” a reference to the government’s leading infectious disease expert, Dr. Anthony Fauci, who is a proponent of the kinds of public health mandates and restrictions on everyday activity that many Republicans have opposed.

“If they can violate your freedom on this issue, they are going to violate your freedoms on other issues,” Mr. DeSantis said.

Mr. DeSantis also talked up his work as governor of Florida putting into effect policies that borrow from Mr. Trump’s agenda. He spoke of his efforts to ensure “election integrity” by signing legislation that limited the distribution of absentee ballots, and of his refusal to help the Biden administration resettle undocumented migrants apprehended at the southwestern border in Florida.

Mr. Trump did not speak at the event in person but recorded a video message played at the conference on Saturday morning in which he predicted banner years ahead for the party. “We will win back the House,” he said. “We will win back the Senate. We will win back in 2024 that beautiful white building.”

In an interview, Mr. Christie said he had told Mr. Trump in private everything he said from the stage on Saturday. “He gets to decide what role he wants to play,” he said, adding that he hopes the former president would opt to play a more constructive one than he has recently. Mr. Trump has, for instance, warned that Republican voters wouldn’t show up at the polls unless the party’s elected officials embrace his lies about voter fraud.

“But anybody who’s talking about the past in this election is a loser,” Mr. Christie said. “They’re just going to lose because the public doesn’t want to see that.”

In addition to Mr. Christie, the other Republican who urged his party in unambiguous terms to get past Mr. Trump’s false and repeated insistences of being cheated of victory was Gov. Chris Sununu of New Hampshire.

Speaking to the optimism in the room, Mr. Sununu offered hope but also a reality check. “This week was a terrific week,” he said, “but if you think this week is going to carry us for a year, you’ve got another thing coming.”

He cited a conversation he said he had recently with a Trump supporter he tried to dissuade from focusing on last year: “Somebody asked me, ‘Well what about the election in 2020?’ I said, ‘Don’t worry about the election. That’s history, man.’”

He added, “If you are sitting here talking about 2020, or you are worried about who’s going to run in ’24, you are missing the boat.”