Jubilant conservative donors gathered in celebration in Washington DC have been promised a sweeping set of early reforms under the Trump presidency, from tax cuts across the board, to a “lock, stock and barrel” repeal of Barack Obama’s health care law.

Vice-president elect Mike Pence, whose ideological conservatism is as sharply drawn as Donald Trump’s is vague, told an audience gathered to support a leading rightwing thinktank to expect tax cuts by spring, the strengthening of the US’s military might, and the appointment of a new conservative justice to the supreme court.

In the presidential ballroom of Donald Trump’s new Washington DC hotel, his vice-president elect tantalized a room full of wealthy conservative patrons on Tuesday night with the prospect of what could be achieved under Trump’s administration.

During a reception for the Heritage Foundation, held under the sweep of chandeliers and amid gilded decor, Pence declared a “mandate” to lead the country as he sketched in broad strokes the administration’s vision for its first few months in power.

“We are just 44 days away from when Donald Trump will be inaugurated as the 45th president of the United States of America,” Pence said before the meal was served at the Heritage Foundation’s President’s Club, an annual affair to honor the “nation’s most committed conservatives” – top-tier donors who give at least $1,000 annually to the foundation. “He did it.”

Pence did not address the deep divisions roiling the country in the wake of Trump’s surprising electoral win. Hillary Clinton, the Democratic presidential nominee, is currently leading the popular vote by more than 2.6m votes.

Her lead has raised questions about whether the president-elect truly has a “mandate” to lead the country as his supporters have said.

But on Tuesday night, the presidential ballroom was reserved for celebrating conservative gains.

Before Pence spoke, John Fogarty, the foundation’s vice-president for development, greeted the crowd of “deplorables”, drawing raucous cheering and applause.

The organization’s president Jim DeMint, a former-senator and Tea Party favorite, took the stage, marveling at the symbolism of the evening.

“I’m trying not to be too giddy,” DeMint said. “There’s something really sweet about standing in a Trump hotel just a few blocks from the White House introducing a great friend of mine and his wonderful wife Karen who are going to be the next vice-president couple of the United States.”

Trump’s DC hotel, a century-old Post Office pavilion that opened this year, has been singled out as one example of a possible ethical quandary for the incoming president, with reports of at least two foreign nations hosting parties at the hotel.

Experts have said Trump’s tangle of businesses and properties poses an unprecedented financial conflict. Trump has said he would soon take himself “completely out of business operations”, without giving further details, and would elaborate on those plans in a speech next week.

Since its founding in 1973, the Heritage Foundation has minted policy prescriptions for the Republican party. During the election campaign, Trump relied on their guidance to draw a list of potential supreme court nominees. He also drew on the organization’s reports and resources to help form his tax and defense policies.

Pence, who said he spoke regularly with DeMint, pledged that the Trump administration would continue to source conservative ideas from the foundation.

Earlier on Tuesday, Pence met with congressional leadership at the Capitol. After the meeting, Senate majority leader Mitch McConnell told reporters that repealing Obama’s signature healthcare law would be “the first item up in the new year”. Pence affirmed that view on Tuesday night, saying Republicans would begin immediately the process of replacing it with “free-market solutions”.

Trump ran on a campaign promise to repeal Obamacare but has said in interviews since the election that he would prefer to replace the law. The incoming Senate minority leader Chuck Schumer scoffed at the suggestion, challenging Republicans to try to repeal Obamacare without a replacement.

“Bring it on,” Schumer said on Tuesday afternoon.

As was often his role on the campaign trail, Pence sought to reassure Republicans who are still jittery about Trump’s commitment to a conservative agenda.

“Both of us were raised to believe that to whom much is given much will be required,” Pence said, adding with a touch of humor: “For him, that meant that the kid from Queens went to Manhattan island and built tall buildings.”

Pence, who said again of himself that he is “a Christian, a conservative and a Republican – in that order”, reminded the crowd that the work begins the moment Trump’s hands touch the bible on 20 January.

“We’ve got work to do,” Pence said. “Enjoy your dinner. Then roll your sleeves up.”