OXON HILL, Md. — President Trump makes a triumphant return Friday morning to the Conservative Political Action Conference, the annual conclave of establishment Republicans who once viewed the party’s surprise standard-bearer as a noisy interloper.

In the days leading up to his appearance, White House officials and Mr. Trump’s surrogates invited comparisons between the president and another former entertainer who crossed over from the party’s margins to define conservatism in his time: Ronald Reagan.

He will be the first president to address the group in his first year in office since Mr. Reagan made an appearance in 1981.

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Vice President Mike Pence, in a well-received speech delivered Thursday night at the main ballroom of the Gaylord National Resort and Convention Center just south of Washington, compared Mr. Trump’s ability to communicate directly with voters to Mr. Reagan’s skills. A White House news release cited Mr. Reagan’s 1974 “city on a hill speech” to the conference.

Friday’s return is especially sweet for Mr. Trump, who had been shunned by the party’s mainstream establishment for years. He skipped the conclave last year, citing his need to campaign in Kansas and Florida, a move many at the conference interpreted as a snub.

But his victory in November has changed the dynamic drastically and recast his relationship to the party’s establishment — so much so that Kellyanne Conway, Mr. Trump’s former campaign manager and now a White House adviser, jokingly referred to CPAC as “TPAC” at her appearance here on Thursday.

That was not always the case. Mr. Trump’s first appearance came in 2011, when he was considering a run for president, and it was viewed more as a curiosity than a must-see speech. Subsequent appearances in 2012, 2013 and 2015 were better received.

Mr. Trump’s approval numbers remain at historic lows for any president at this point in his term, but his support levels among Republicans remain high, with most polls showing him with approval ratings of over 80 percent among the party base.

Conference attendees on Thursday seemed overwhelmingly supportive, with periodic chants of “Trump!” erupting between the speeches and the red signposts of “Make America Great Again” hats dotting the gathering.

But the festive atmosphere obscured a jarring political shift from years past, when many mainstream conservatives supported positions that are now anathema to Mr. Trump and his supporters — including free trade, new public spending on infrastructure and comprehensive immigration overhaul.

On Thursday, Mr. Trump’s chief strategist, Stephen K. Bannon, laid out that new, harder-edged vision for the movement in a rare public appearance. Accompanied by the White House chief of staff, Reince Priebus, Mr. Bannon said the flurry of executive orders during Mr. Trump’s first month in office was just the beginning of a drive to quickly fulfill campaign promises on border security, on immigration restrictions, on a tax overhaul and to slash government regulations.

“This is the main thing that the mainstream media or the opposition party never caught, is that if you want to see the Trump agenda it’s very simple,” he said. “It was all in the speeches. He’s laid out an agenda with those speeches, with the promises he made, and our job every day is to just to execute on that. He’s maniacally focused on that.”