The record numbers of Americans voting by mail in the upcoming US election all but guarantees there won’t be a result on November 3.

According to the US Elections Project at the University of Florida, at least 30 million votes either by mail or in person had been recorded in 44 states and Washington DC as of Tuesday (Australian time).

In 2016, there were only 5.9 million early votes by October 23, 16 days before Election Day.

While President Donald Trump has repeatedly raised fears of fraud involving mail-in voting, it is being widely used for safety reasons due to the coronavirus pandemic.

But that doesn’t mean the results will be flawed or fraudulent. In fact, the President himself has also applied to vote by post.

So who is voting early?

CEO of the United States Studies Centre’s Professor Simon Jackman says Democrats are overwhelmingly taking advantage of early voting – and it bodes well for Joe Biden.

“Those votes are off the table. That means that’s someone less you have to mobilise and get out and persuade to vote,” Professor Jackman says.

“On balance it’s a better signal for the Democrats, it shows the level of enthusiasm. That’s the biggest thing it signifies. There could be just as much enthusiasm for Republicans, but we don’t know until the day.

But election officials in key battleground states have warned it might take days to count the votes, given the surge of ballots sent by mail.

A Miami voter shows displays the sticker she received after casting an early ballot.

Because processing mail ballots is more laborious than in-person voting, states that haven’t updated their laws and systems for the different workload will see inevitable delays.

Professor Jackman says Republicans are more likely to vote in a more conventional way, by showing up at polling places on Election Day.

But it’s a riskier strategy.

“Until that vote is cast, there’s a chance it might not get cast or it will go to someone else,” he said.

“The other risk is that COVID-19 is getting worse, not better. Plans to vote on Election Day are more at risk from that.”

Which states will be the bellwethers?

A presidential election hasn’t been left in limbo since 2000, when ballot irregularities in Florida led to weeks of chaos and court fights.

While each state runs its own process, mail ballots can take longer to count. In some states, the ballots can be accepted several days after Election Day, as long as they are postmarked before polls closed.

Joe Biden’s home state Pennsylvania will be a major battleground – particularly as the state has laws that forbid processing mail ballots until Election Day, guaranteeing the count will extend well past that night.

“Trump surprised everyone in winning Pennsylvania. It had gone to Obama in 2012 and Trump only won it by a hair’s breadth,” Professor Jackman said.

“It’s a really important state for him to hang on to. Joe Biden talks about his working-class credentials growing up in Scranton.”

The other major prize will be Donald Trump’s adopted state of Florida which he must win if he wants another four years in office.

On Monday, Floridians were lining up on the first day of their early polling in the battleground state.

Social media posts showed lines of voters in some of the 52 of Florida’s 67 counties that began in-person early voting on Monday local time, suggesting similarly high levels of enthusiasm as seen in other early voting states this year.

Hundreds of people, most wearing face masks, stood in the pouring rain in the morning outside the public library in Coral Gables, a majority-Hispanic city near Miami.