They always had Mike Pence.
Deeply religious, strait-laced and unfailingly loyal, the vice president was supposed to be an insurance policy for the social conservatives and evangelical Christians who found President Trump too crude, domineering and politically unreliable.
But Mr. Trump’s hospitalization for complications from Covid-19 raised an unsettling question about Mr. Pence, and more broadly about the future of the party, for Republicans who have grown used to the alpha, tweet-first, consider-precedent-later leadership of the president.
In recent days, no Republican, including Mr. Pence, was able to fill the giant void left by the president’s brief disappearance from the public eye. Mr. Pence remained largely out of sight as Mr. Trump refused to delegate his powers, denying the man next in line to the presidency a moment to shine.
Ahead of the vice-presidential debate on Wednesday evening, the highest-stakes event Mr. Pence has faced in a political career he does not want cut short before he has a chance to run for president himself, it is not at all clear that his reserved and dutiful approach, conservative in both style and substance, can substitute for the sheer force of personality that Republicans now associate with the political success they have had under Mr. Trump.
One unforeseen consequence of Mr. Trump’s dominance of the Republican Party has been how thoroughly he shattered the expectations of religious conservatives — the cornerstone of the party’s base — for a president’s conduct and leadership. The mold for appealing to those voters used to look a lot like Mr. Pence: an evangelical Christian who has unabashedly taken up causes dear to the activist right, like opposition to abortion and gay rights and dismantling government regulations on businesses, schools and churches.
One of the biggest questions hanging over Mr. Pence’s future is whether Republican voters in a post-Trump world will embrace a candidate who seems to embody what the party thought it needed in a nominee before Mr. Trump came along, and who lacks the fearlessness and audacity that many conservatives say Mr. Trump demonstrated as he pushed policy and the courts further to the right than any president in recent history.
“There are some qualities that Mike Pence has that I’ll continue to hope and pray that Donald Trump adopts — and the reverse is true as well,” said Tony Perkins, the president of the Family Research Council, a pro-Trump, social conservative group. “There are qualities that Donald Trump has that I hope and pray Mike Pence adopts. And that is that he picks up a little bit of the fight and courage that Donald Trump shows on a daily basis.”
Mr. Pence now finds himself in a position that he likely never could have imagined four years ago. The steady, paint-inside-the-lines manner that social conservatives once found so reassuring in him might be devaluing his political stock today.
“The Trump years have made his life more difficult, not less,” said Peter Wehner, a former White House speechwriter who served in three Republican administrations. He has distanced himself from the evangelical conservative politics he once considered himself a part of over the movement’s alignment with Mr. Trump.
“For one thing, somebody like Pence in the past would have had a certain appeal to evangelical voters that is less strong now because evangelicals, in embracing Trump, have changed their character,” Mr. Wehner said, adding, “The kind of appeal that a guy like Pence had is just not as great.”
Mr. Trump’s health problems, coming on top of a looming election that polls show Republicans at considerable risk of losing, have added greater urgency to the debate inside the Republican Party over its future and whether its next leader should be someone who emulates Mr. Trump. No small number of conservatives believe their political victories over the last four years would have been impossible without Mr. Trump’s defiance of political norms and his frequent disregard for civility and compromise in domestic and foreign affairs.
As evidence, they point to actions Mr. Trump has taken that they said other Republican presidents would have been too restrained to pull off, no matter how conservative they were, such as moving the American embassy in Israel from Tel Aviv to Jerusalem and pulling out of international agreements such as the Paris climate accords and the pact on nuclear development with Iran.
“It took Trump’s determination to get these things done,” Mr. Perkins said.
Republican elected officials have tried to copy Mr. Trump’s renegade style, with varying degrees of success. It’s difficult for most politicians to do. Some conservatives said that when they look at the senators and governors who are considered to be the next generation of Republican leadership, they do not see anyone capable of replicating Mr. Trump’s style and having the same command over the public’s attention.
“There has to be a level of shamelessness that is not easy to achieve,” said Yuval Levin, director of Social, Cultural and Constitutional Studies at the American Enterprise Institute.
If most of the stylistic aspects of his leadership can’t be copied, there are still some things about him that could carry over. One, said Mr. Levin, is the skepticism that Mr. Trump sows about government institutions, from the intelligence services he accuses of undermining him to the Federal Reserve he claims is stifling economic growth. Doubt about the trustworthiness of the country’s governance has been an animating feature of the American right, most recently as a force behind the Tea Party movement in 2009.
Trump followers and Tea Party supporters, Mr. Levin said, “begin from the premise that the institutions are all corrupt and they turned against us. And that is the essence of populism that politicians are going to continue to emulate.”
That could help someone like Mr. Pence, who despite holding public office first as a member of Congress and then as governor of Indiana, will likely benefit from the association with Mr. Trump and his attacks on the federal government.
Looking at the kinds of Republicans who have been elected since Mr. Trump took office — Gov. Ron DeSantis of Florida, Gov. Brian Kemp of Georgia, Senator Josh Hawley of Missouri — all have borrowed elements of Mr. Trump’s populist angst. That suggests that whatever the future of the party is, even if Mr. Trump is no longer its leader after 2020, his imprint will remain for a long time. And it is impossible to tell how far Republicans will go in adopting Mr. Trump’s anti-immigrant, race-baiting talk, which has an undeniable appeal with parts of his base but could become even more politically toxic as the country’s demographics grow more diverse.
“Trumpism won’t go away even if he has a bad election,” said Pippa Norris, a professor of comparative politics at Harvard University. “What’s to say that other Trumpists in the party won’t replace him?”
As long as enough Republicans believe that Mr. Trump’s approach to winning the presidency was the right one, it will be hard to drive his legacy out of the party, Ms. Norris added. “It’s very difficult to change the perception of how you won the battle last time.”
The question for more traditional Republicans like Mr. Pence is whether their relatively restrained styles will seem like a comfort to voters who are eager to return to something more normal and familiar.
Some conservatives said there was little use judging Mr. Pence’s likelihood of succeeding Mr. Trump as the leader of his movement, at least not with comparisons to a president unlike any in American history.
“Trump is a historical anomaly, a once in a lifetime political phenomenon,” said Ralph Reed, a veteran Christian conservative strategist. “When F.D.R., John F. Kennedy and Reagan left the stage, there was no one like them. The same will be true of Trump. We won’t see anything like this again.”