President Donald Trump has been renominated as the GOP’s presidential candidate.

Republicans made it official during a scaled-back roll call vote on Monday at the Charlotte Convention Center in North Carolina.

Trump faces a difficult fight for re-election as he continues to deal with the fallout of the coronavirus pandemic, which has killed about 177,000 people in the United States, ravaged the economy and upended nearly all aspects of life. The president’s bid for a second term also continues to be shadowed by protests throughout the nation over police brutality and racial injustice.

Now that delegates have completed the task of formally renominating Trump, much of the remaining convention business will shift to the Washington, D.C., area. Trump is scheduled to deliver his acceptance speech from the White House South Lawn on Thursday evening.

On Monday, Trump told delegates that the only way Democrats can win is “if this is a rigged election.”

Until he won, Trump also warned that the 2016 election was going to be rigged.

He says Americans know how to keep themselves safe from the coronavirus and can go to the polls, eliminating the need to mail in their ballots. He said, without providing evidence, that that creates fraud.

Voter fraud has proved exceedingly rare. The Brennan Center for Justice in 2017 ranked the risk of ballot fraud at 0.00004% to 0.0009%, based on studies of past elections.

Trump says other votes will be “harvested” by people going door-to-door to collect ballots that voters have not submitted. In addition, he says some states are not verifying signatures on ballots. He did not provide evidence for those claims.

Democrats nominated former Vice President Joe Biden as their presidential candidate at their all-virtual convention last week.

On Monday, Republican National Committee Chairperson Ronna McDaniel said, "This is a historic moment. As we make official the nomination of Donald Trump and Mike Pence as our nominees for President and Vice President of the United States, today's events reflect the unified support the Trump-Pence ticket has from Republicans along with Independents and discerning Democrats all across America. Our party is unified. Our supporters are energized and now we will go forward confident in our cause of re-electing President Trump and Vice President Pence in 70 days from now."

Elected officials who are expected to speak include Senate Majority Leader Mitch McConnell, House Minority Leader Kevin McCarthy, Senator Tim Scott, Senator Joni Ernst, and South Dakota Governor Kristi Noem, and Trump administration officials including Secretary of State Mike Pompeo and former United Nations Ambassador Nikki Haley.

Others who are set to speak at the RNC include Donald Trump Jr.; Ivanka Trump; Mark and Patricia McCloskey, the St. Louis couple who were captured in a viral photo pointing guns at Black Lives Matter protesters; Alice Johnson, the grandmother pardoned by Mr. Trump after facilitation from Kim Kardashian West; Andrew Pollack, whose daughter Meadow was killed in the Parkland school shooting and Nick Sandmann, the Covington Catholic High School student featured in viral video.

Related: Biden Vows to Defeat President Trump, End U.S. 'Season of Darkness' 

Meanwhile, the Biden-Harris campaign has released a new ad, slated to air during the Republican Convention.

(The Associated Press, CBS News contributed to this report.)