With three weeks until election day in the United States more than 10 million Americans have already voted and CGTN analysis suggests Joe Biden has pulled further ahead of Donald Trump in the national polls.

Interactive page: X Factors in the U.S. Election

Here are the highlights from the past seven days.

Trump returned to the White House after his COVID-19 hospitalization, released a series of videos, conducted phone or recorded interviews with Fox News, addressed a crowd on the South Lawn on Saturday, and then got into a spat with Anthony Fauci before returning to the campaign trail in Florida on Monday.

The president, desperate to return to in-person events, insisted he was "immune" from the virus on Sunday in a tweet which was flagged for spreading "misleading and potentially harmful information" as the U.S. continued to report over 40,000 new COVID-19 cases per day.

Confirmation of a negative test did not come until Trump was en route to Monday's rally, the first of a series of swing state campaign stops – Axios reported that the Republican wants to hold a rally every day until November 3.

Polling numbers for Trump have gone from bad to worse since the first presidential debate and his COVID-19 diagnosis.

Seemingly low on funds, the president's campaign is cutting advertising spending and hoping for a free media boost from rallies just as Biden, flush with cash, broadens his own ad buys: the Democrat splashed out $40 million to Trump's $23 million over the past week.

Florida is yet again shaping up to be the race to watch. It's one of few key states in the age of mass mail-in voting likely to report on November 3, and if Biden wins its 29 Electoral College votes, the election will be as good as over.

CGTN analysis of public polling indicates the former vice president is up by 3.4 points in Florida and over eight points nationally, with female, older and suburban voters moving towards him. Biden has built up a lead with seniors, the most reliable voting bloc, as the pandemic has progressed.

While the first presidential debate looks to have hurt Trump in the polls, the only lasting impact from the vice-presidential clash between Democrat Kamala Harris and Republican Mike Pence is the slew of memes that emerged after a fly perched for two minutes on the vice president's head.

Snap polls suggested Harris was the winner of a low-key debate which was quickly forgotten as the president returned to center stage. Whether Biden and Trump will square up again in person remains unclear – the president has refused to debate virtually and so the second event, scheduled for this week, has been cancelled.

The third planned debate, now the second, is still due to go ahead on October 22 and could be the final opportunity for Trump to try to knock the risk-averse Biden campaign off course.

Video: Wang Zengzheng and Zhou Tingyu

Script: John Goodrich

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