Barbara Dwyer wanted to go all in with Donald Trump in the 2016 Republican presidential primary race but couldn’t shake her hesitation and instead cast her vote for Sen. Marco Rubio.

A year into the Trump presidency, the 36-year-old stay-at-home mother of five said she is “a million percent” happy that she got it wrong.

“I love Sen. Rubio, I respect what he does, but Donald Trump is bringing a lot of energy to the party, and he is getting things done, which has not happened in quite some time,” said Mrs. Dwyer, attending the Conservative Political Action Conference last week just outside the Beltway. “A lot of people are coming around because they are happy and they are seeing the direction and excited about where we are headed.”

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Mrs. Dwyer’s sentiment is the latest evidence of how firmly Mr. Trump has grasped the reins of the American conservative movement, erasing doubts about his own bona fides even as he draws the political right toward his own beliefs.

“Remember when I first started running?” Mr. Trump said as he kicked off his speech to CPAC on Friday. “I started running, and people say, ‘Are you sure he’s a conservative?’ I think, now, we’ve proved that I’m a conservative, right?”

The numbers back him up.

A CPAC/Washington Times poll of more than 1,100 attendees found that 93 percent of conservatives approve of the job Mr. Trump has done over his first year in office — up from 86 percent last year.

The crowd also was more optimistic about the direction of the nation than they were a year ago, with 75 percent saying the nation is on the right track, compared with 44 percent last year.

Conservatives are increasingly pushing for congressional Republicans to take their cue from Mr. Trump, with 79 percent saying Republican majorities in the House and Senate should be doing more to support the president — up from the 67 percent in last year’s poll. Just 4 percent of the conservatives said Congress should try to stymie Mr. Trump’s agenda.

“The conservative movement has found a new leader,” said Jim McLaughlin, who ran the poll.

In prior years, CPAC provided conservatives with a chance to reminisce about former President Ronald Reagan, dog-pile on President Obama, and lament how liberals and moderate Republicans had undercut the nation’s moral and fiscal underpinnings and tarnished the nation’s place on the world stage.

The confab also served as a showcase for the party’s biggest stars and home of the highly anticipated presidential preference straw poll, which Sen. Rand Paul of Kentucky won in 2013, 2014 and 2015.

Sen. Ted Cruz of Texas captured the honor in 2016, the same year that Mr. Trump abruptly pulled out of the event amid reports that activists planned to stage a walkout to show their support for Mr. Cruz and concerns about Mr. Trump.

But little more than a year into the Trump presidency, those concerns have evaporated, with conservatives cheering the first major overhaul of the federal tax code since Reagan, appointing Neil Gorsuch to the Supreme Court and beginning to move the U.S. Embassy in Israel from Tel Aviv to Jerusalem.

William Temple, a CPAC regular known for dressing up in Revolutionary War garb, was behind the plan to walk out on Mr. Trump two years ago.

“I was a big Cruz supporter, but Trump has done everything that I wanted Cruz to do and more, and he has accomplished it in a year,” Mr. Temple said.

He said the president has been so successful that it has forced him to rethink his views on leadership.

“Why would we ever elect career politicians to do anything? We should be getting private-sector people, ex-military, whatever, people who actually have sacrificed for the country,” he said.

Mr. Temple said he also is happy that his top pick for the job lost and “as a matter of fact, I think Ted Cruz is looking at it and realizing the same thing.”

Mr. Cruz said nearly as much, telling the CPAC crowd that Mr. Trump’s “record of delivery has been remarkable.”

As far as conservatives are concerned, the biggest stains on Mr. Trump’s record are his uncouth behavior and his decision to sign off on a bill last month that increased spending over two years by $300 billion.

“In terms of his character, he seems fundamentally flawed. I will support a primary candidate, whoever it is, if a primary candidate runs in 2020,” said 22-year-old Joey Pickens. “I just think he’s an immoral person, and I don’t want him representing our country with his attitude and his values.”

That was a decidedly rare opinion among the conservative grass-roots leaders who make up CPAC.

“I was a Ted Cruz supporter, and the concerns I had was [Mr. Trump] not keeping his promises on a lot of things,” said 34-year-old Robert Sinnott. “But he seems to be doing a fairly good job on that. I am happy he has repealed a lot of different regulations like he said he would. I am happy about the tax cuts, and I didn’t really like him tweeting at first, but it seems to rile up the left, so it is good in a way.”

Rick Zimmerman, who supported Wisconsin Gov. Scott Walker and then Mr. Cruz in 2016 before voting for Mr. Trump in the general election, said the biggest barriers to getting more of the Trump agenda passed have been wayward Republicans such as Sen. John McCain of Arizona.

“If he had a better Congress, he’d do more,” said Mr. Zimmerman, 71.

Mr. Zimmerman said he also is happy that he failed to envision Mr. Trump governing in such a conservative fashion.

“I just didn’t think he was going to be that kind of conservative,” he said. “I was wrong.”