The "Million MAGA March" was heavily promoted on social media, raising concerns that it could spark conflict with anti-Trump demonstrators, who had gathered near the White House in Black Lives Matter Plaza for weeks.
Mr Trump persists with his claims and complaints even though a broad coalition of top government and industry officials has declared that the November 3 voting and the following count unfolded smoothly with no more than the usual minor hiccups.
Biden won the presidency by refusing to embrace his party's most liberal causes, government-funded health care under "Medicare for All" and the Green New Deal, a collection of proposals to drastically remake the economy to combat climate change.
Trump has not yet conceded the race - and may never actually do so, NBC News quoted his aides as saying.
The demonstrators were also identifiable by their lack of face-masks as many participants rejected measures to contain the spread of coronavirus.
"We have a president of the United States, that is so very important whether you are in the majority or the minority if the president is of your party you have more power", she said during a news conference. The president, meanwhile, continued to make false claims on Twitter that the election was being "stolen" from him.
Many COVID-19 patients later develop mental illness, study finds
The findings are likely to be the same for those afflicted by COVID-19 worldwide, the researchers said. This was about twice as likely as in other patient groups during the same period.
What's happening with the transition?
The choice of Klain underscores the effort the incoming Biden administration will place on the coronavirus response from day one.
Without a GSA signoff, transition funds and other resources including access to intelligence briefings cannot flow to Biden and his team, but Murphy has refused to budge.
"President-elect Biden has a wealth of not just experience but contacts, people he's worked with in the past, people who he can engage with to get briefings, have discussions with in the national security field, and he will certainly be doing that", she asserted. "It's imperative that our team and our experts have that access". That's going to take some time.
Trump's projected win in North Carolina added 15 electoral college votes, retaining the state he won in 2016.
The President is yet to concede the election, despite numerous news networks declaring Mr Biden the victor, and several Republican candidates have followed his lead in refusing to concede.