LAS VEGAS — Everybody loses some of their inhibitions in Las Vegas. Even Elizabeth Warren.

This is where the Democratic senator from Massachusetts shrugged off her reluctance to criticize rivals and eviscerated them during a debate, landing precision blows one after the other. This is where she accepted the help of a super PAC, reversing a central tenet of her presidential campaign about the corrupting power of money. And this is where it started to look like she was having fun for the first time in months, just ahead of Saturday’s Nevada caucuses.

After moping two weeks ago through New Hampshire, where she stressed to audiences that she hasn’t spent her career pining for the White House, she was suddenly making changes that could expand the possibility that she gets there.

Allies say Warren’s demeanor changed after disappointing results rolled in from gray and snow-covered New Hampshire. Already upset with herself for a lackluster New Hampshire debate and down about her disappointing third-place finish in Iowa, she made a case to her staff that this was the time to fight.

“There’s going to come a time when it is clear what’s going to happen in this contest, but that time is not now,” she said, according to a person familiar with the call who spoke on the condition of anonymity because the person was not authorized to discuss it. “We are nowhere near that moment. We are not close. We’re not even within shouting distance.

“These are the moments we find out who we are.”

Her new approach might be too late. Nearly as many Nevada caucus-goers participated in early voting before her breakout debate as the total turnout four years ago, meaning a massive chunk of the electorate here weighed in before seeing Warren sparkle onstage. Hundreds of thousands already have cast their ballots in California, the top delegate prize on March 3.

More importantly, the dynamics of the race so far continue to drastically narrow her path: Sen. Bernie Sanders (I-Vt.) has largely consolidated support from the left. Warren hasn’t significantly expanded her support among moderates, failing to benefit from former vice president Joe Biden’s slide in the polls. She also has struggled for support from the white, college-educated voters backing Sen. Amy Klobuchar (D-Minn.) and former South Bend, Ind., mayor Pete Buttigieg.

Financially, her campaign came closer to the brink than was publicly known before the Iowa caucuses on Feb. 3. New financial reports show the campaign took out a $3 million line of credit and drew out $400,000 that it ended up not using. She ended last month with just $2.3 million on hand but has so far raised $17 million in February, including a huge bump after her debate here.

“The central question for Warren is does a strong performance by her bring some of the liberals who are on the fence between her and Sanders back to her?” said Neera Tanden, the president of the Center for American Progress, a liberal think tank, who has not backed any of the presidential candidates. “If you’re a very liberal person and you’re asking, ‘Who can best take on Trump?’ she reassured you on that,” Tanden said.

Warren and her allies believe the muddled results so far mean there’s still time for her to win. Just 4 percent of the delegates needed to clinch the nomination will have been awarded after South Carolina votes on Feb. 29. But the challenge rises astronomically days later, on March 3, when more than a third of the delegates will be distributed after voting in more than a dozen states.

Warren’s schedule provides a clear sign that she plans to fight hard in the hope of running up the score in liberal pockets of the country on Super Tuesday.

She plans to leave Nevada on Saturday — likely before caucus results are announced — to headline a rally in Seattle and then skips to Denver on Sunday, hitting the large, expensive media markets in two states that vote in March. After a stop in South Carolina, she plans to travel to California and other Super Tuesday states.

Warren’s demeanor has brightened markedly since Wednesday’s debate here, where she was sharply critical of billionaire candidate and former New York mayor Mike Bloomberg and also delivered lancing blows on other rivals.

“So after the debate last night, are we ready to make a change? How about some big structural change?” Warren exhorted a group of cheering volunteers packed into one of her campaign offices in a Las Vegas strip mall.

“Last night was a lot of fun,” she added, and then rehashed her critique of Bloomberg’s stop-and-frisk policing policy.

Later, during a CNN town hall Thursday night, she pressed the case further, reading from a legal document she had prepared for Bloomberg that would release women from nondisclosure agreements reached after claims of harassment involving him or his company. (Bloomberg agreed Friday to discard three agreements if the women involved want to be freed from them. He said those were the only ones that pertained to his own behavior.)

“I used to teach contract law,” said Warren, a rare reference to her time as a law professor. “I wrote up a release and covenant not to sue, and all that Mayor Bloomberg has to do is download it — I’ll text it — sign it, and then the women, or men, will be free to speak and tell their own stories.”

She took out a piece of paper and read aloud.

It was the kind of attention-seeking stunt that she has avoided for the past year, instead dutifully focusing on policy and her organization’s regular releases of dense, footnoted position papers that made it feel more like a think tank than presidential campaign.

“She’s engaging in the political stakes for what they are and not what she wants them to be,” said Adam Jentelson, a Warren ally. “She’s playing to win now. In a good way.”

But her reversal on accepting help from super PACs opened her up to accusations that she had bent her principles to boost her candidacy.

On Thursday night, at the town hall, she made a tortured case that her embrace of a super PAC wasn’t inconsistent with her campaign beliefs.

“So from the first day I got in this campaign, I said to anybody who runs for president, ‘Let’s do this without super PACs. Let’s all agree. Before they’ve gotten into it, before people have invested money in this, let’s all just agree we will all say no super PACs,’” she said on CNN. “Nobody took me up on it. . . . Not a single other candidate would agree with me. So I haven’t changed my position.”

She did not explain how her new stance squares with a section of her campaign website, which in capital letters says she “REJECTS SUPER PACs.”

The Persist super PAC benefiting Warren has spent $1 million in South Carolina on TV ads, according to its spokesman. It also put $1 million into ads running in Nevada. The group is planning a Super Tuesday strategy.

The super PAC will use tools that Warren has eschewed, including polling, to determine which TV commercials move the most voters.

In her presidential campaign, Warren has boasted of shedding consultants and a pollster she used in her Senate races. The super PAC is reaching out to some of those staffers, potentially reconstituting some of the team that helped her win previous contests.

Warren’s debate move marked the second time in her campaign that she has taken bold steps with her back against the wall. When Warren first entered the race, she slumped amid controversy over having claimed Native American ancestry. Her fundraising was weak and polling had her in single digits.

She responded by throwing aside caution on some issues that felt tricky at the time, including becoming the first presidential candidate to call for the impeachment of President Trump, refusing as a protest to participate in a Fox News town hall and, perhaps most importantly, dismantling her high-dollar fundraising operation. The moves set her apart in a crowded field.

Now Warren is also altering her message, moving away from casting herself as a unity candidate and returning to the image of a fighter.

“Her mistake in New Hampshire was to campaign as the unifier. She will be the unifier in the end; in the meantime, she needs to be a fighter in order to continue to build her own base,” said Rep. Jamie B. Raskin (D-Md.), who has endorsed Warren. “I think she can become a unifier at the convention, but she has to be a fighter during the campaign. And she was a prizefighter” at the debate, he said.

Raskin said her debate performance buoyed the spirits of her endorsers.

“People were so excited,” he said. “Everybody was writing about how she had transformed the campaign, she had revitalized everybody’s spirits and she had really punched through to the top tier of the race.”

Warren allies timed the real change in her to the results in New Hampshire, which showed she would not win a single delegate from her next-door state.

“She gets this kind of underdog determination,” said one Warren ally, who saw her that night but would speak only on the condition of anonymity to discuss a private moment. Her demeanor, the person said, became: “I’m not going to go down without a fight.”

In her conference call with staff members that night, she offered an upbeat assessment.

“These are the moments when we remember that knockdowns make us stronger, [that] challenges build muscle,” Warren told them on the phone call. “Hear this straight from me to you, I believe in you and I believe in what we can do together.”