Liberal Democrats and progressive activists have grown wary of the state of the 2016 presidential race, chafing at Hillary Clinton’s big-tent courtship of Republican leaders they have long opposed and fearing the consequences of shaping the contest as a referendum on Donald Trump.

While few have questioned the electoral strategy of bringing Republicans into the fold by casting Trump as a singular threat to democracy, both skeptics and some admirers of Clinton have come to view her decisive advantage in the polls with mixed emotions.

She may win by a mandate-level margin, they say. But what, exactly, would the mandate be for?

In a matter of weeks, beginning with the party conventions, the policy-driven debates that animated the Democratic primary race have largely disappeared from the political foreground, giving way to discussions of Trump’s temperament, his inflammatory remarks and even his sanity.

“If she’s going to get anything done as president, she is going to have to have a mandate,” said Robert B. Reich, a secretary of labor in Bill Clinton’s administration who supported Sen. Bernie Sanders in the primary.

The subject of Trump’s temperament was unavoidable, Reich said, “but temperament doesn’t give you a mandate to do anything.”

Hillary Clinton’s dogged pursuit of Republican votes has especially rankled progressives, and highlights the divisions within the Democratic Party, even as they see a victory more likely. They have grumbled at her eager promotion of endorsements from veterans of the George W. Bush and Reagan administrations, including that of John D. Negroponte, a top diplomat and intelligence official under Bush. They worry aloud that Henry Kissinger, of whom Clinton has often spoken fondly, could be next.

“Secretary Clinton’s decision to aggressively court Mitt Romney’s base has her looking more and more like Mitt Romney every day,” said Benjamin T. Jealous, a former NAACP president who initially supported Sanders. “That’s not a good thing.”

By most measures, the Democratic Party’s left flank has had a banner year. Sanders’ primary challenge pushed Clinton conspicuously left, coaxing her into policy shifts on trade and college tuition. The party platform was, by virtually all accounts, the most progressive in history, and Clinton has not made any perceptible changes in substance recently.

Notably, a major economic speech from Clinton Thursday in Michigan would not have seemed out of place in the primary race, with discussions of expanded Social Security, debt-free college and a higher minimum wage.

And on Friday morning, her campaign, sensitive to any suggestion that Clinton might waver on promises to the left, emailed reporters a collection of 22 sympathetic quotes and Twitter posts from left-leaning leaders and organizations.

“She is not just running as the alternative to the other guy. She is running on a progressive policy agenda that she seriously believes will make a difference in people’s lives,” Brian Fallon, a campaign spokesman, said in an email. “If she wins, it will not just mean a rejection of Donald Trump. It will be a call to action on the issues she has championed.”

But the campaign’s chief gambit since the start of the Democratic convention — depicting Trump as a menacing anomaly, disconnected from mainstream Republican thought — has already supplied Trump-averse conservatives with an opening: Even if Clinton wins big, Republicans opposed to Trump’s rise may argue that Americans were not voting for her policy proposals.

Some are not waiting.

“Clinton is not likely to emerge with a legislative mandate,” said Rick Tyler, a former top aide to Sen. Ted Cruz’s presidential run. “She will have to start from zero in terms of selling all her policy proposals. They will not have been sold through this process.”

Tyler, who believes the 2016 election has effectively been decided, predicted a common refrain from Republican legislators next year: “We didn’t see that the people voted for that; we see that the people voted against Donald Trump.”

In interviews, elected progressive leaders, activists and local lawmakers made clear that their top priority remains defeating Trump. Most cautioned that the race was a long way from over, despite a wave of encouraging polls for Clinton.

Still, some liberals fear their leverage has been diminished, though the vast majority of Sanders’ supporters have rallied to Clinton’s side, if sometimes tepidly. If she can win without generating excitement among that already distrustful wing of the party, they reason, she may be less inclined to accommodate it once in office.

“We need the broadest popular front against Donald Trump,” said Bill Lipton, a founder of the Working Families Party. “The challenge for the left is, if that’s all we do, we’re saying anyone one degree to the left of David Duke is OK with us.”

Many of Sanders’ backers believe that two of the principal issues he raised during his primary contest against Clinton — her foreign policy hawkishness and her Wall Street ties — remain central to her political core.

“I fully expected that we would be at war with the Clinton administration, if there is one,” said Jonathan Tasini, a former union leader who challenged Clinton in her Senate primary in 2006. “Once she is elected, I suspect she will go back to being what she is, which is a relatively moderate, centrist, corporate Democrat.”

Helen Gym, a Philadelphia City Council member who supported Clinton in the primary, said the dynamics between Clinton’s team and the party’s activist base reflected “a fragile negotiation.”

“The coalition has to hold together,” she said. “Is a Clinton victory synonymous with a progressive victory? It depends. I don’t think I can give a full yes or no.”

Adam Green, a founder of the Progressive Change Campaign Committee, said Clinton’s efforts to cast a wide net and train voters’ attention on Trump amounted to a “double-edged sword.”

“Republicans in Congress won’t grant as easily after the election that we won a huge mandate on progressive issues, but thanks to Donald Trump, we might have more progressives and majorities in Congress,” Green said. “I’d rather have a Republican minority in denial about what just happened than a Republican majority standing in the way.”

© 2016 The New York Times Company