PHILADELPHIA (WPVI) — Donald Trump spent his first day as president-elect receiving congratulatory phone calls from his defeated opponent, world leaders and President Joe Biden as he began the process of turning his election victory into government.

Trump was trying to keep a low profile and stay out of the public eye after addressing supporters in Florida early Wednesday morning.

Vice President Kamala Harris called Trump to concede the race and congratulate him. Biden, on the other hand, invited the man he fired from the White House four years ago to an Oval Office meeting to prepare to return the keys.

“We feel pretty optimistic about the future of our country,” said Kush Desai, the Trump campaign’s communications director in Pennsylvania.

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He says Trump embraced the importance of the nation early in the race.

“It really speaks to how much he cares about Pennsylvania, how much he loves Pennsylvania and our investment in Pennsylvania,” Desai said.

And now it’s time for Trump to set the wheels in motion for his second term, which includes filling out his cabinet and fulfilling campaign promises to improve the economy, secure the southern border, and release the Jan. 6 defendants.

“America has given us unprecedented and powerful authority,” Trump said in his victory speech.

John Kennedy, a political science professor at West Chester University, says he understands why Trump refers to his agenda as an order.

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“Absolutely,” he says, “it looks like he’ll win a majority of the vote, and Republicans haven’t been able to do that since 2004. So I think he certainly has the right to seek office.”

Trump and Harris said in a phone call Wednesday that the president-elect “commenced Vice President Harris for her strength, professionalism and tenacity throughout the campaign, and both leaders agreed on the importance of uniting the country,” according to Trump spokesman Steven Cheung.

Professor Kennedy says this loss does not necessarily mean a rejection of the Vice President.

“This is a party issue. This goes much deeper than just having one candidate in one election,” Kennedy said.

Trump will also work to fulfill his other big campaign promises, including imposing new tariffs on imports and dramatically reducing the size of the federal government to $2 trillion amid budget cuts.

The Associated Press contributed to this report.