The US presidential elections, scheduled to be held on November 3, are boiling down to a handful of battleground states. There are six states that Democratic candidate Joe Biden must flip to snatch the White House from President Donald Trump.

All of this year’s top swing states — Florida, Pennsylvania, Michigan, North Carolina, Wisconsin and Arizona — went to Trump in 2016, including four which had voted for Democrat Barack Obama in 2012.

Trump will tour five of the key states this week, starting with Florida and North Carolina on Tuesday, in hopes that promises of a quick coronavirus vaccine and booming economic recovery will right his floundering reelection campaign.

Challenger Joe Biden currently leads by an average of 3.2 percentage points in the battlegrounds, according to the RealClearPolitics (RCP) poll aggregate.

Should the remaining 44 states vote as they did four years ago, Biden could flip just the two biggest battlegrounds, Florida and Pennsylvania, and win.

Here is a look at the top swing states:

Pennsylvania

Biden’s birth state is the largest at play in the Rust Belt, a north-central region marked by industrial decline over the past decade.

Trump supporters and volunteers in the state have gone on a overdrive, and are canvassing door-to-door, including in the city suburbs.

Pennsylvania has multiple socio-economic regions and Biden, whose campaign is largely sticking to public health guidelines by organizing primarily online, has poured ad resources into the state.

The big cities in the state are expected to vote heavily for Biden, while the rural west and conservative central Pennsylvania are committed to Trump. The suburbs and the state’s northeast will be critical.

RCP average: Biden leads by 3.9 percentage points

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Michigan

Trump won Michigan by a narrow margin in 2016 and it is being fiercely contested this year.

Trump has visited the Great Lakes state touting an American comeback, but its voters are concerned about the pandemic’s impact on the economy, and the president’s response.

Democratic Governor Gretchen Whitmer has clashed with the president, and her enforced lockdowns have angered conservatives, many of whom arrived with guns to protest this summer at the state capitol.

RCP: Biden by 2.6

Wisconsin

In 2016, Trump’s opponent opted against campaigning in America’s dairyland, and voters punished her for it.

This year Democrats made a point of highlighting Wisconsin, locating their national convention there last month, although the gathering moved online over coronavirus concerns.

Trump and Biden both visited protest-hit Kenosha last week as they offered contrasting visions, while Vice President Mike Pence and Biden running mate Kamala Harris each campaigned in the state Monday.

RCP: Biden by 5.0

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Florida

The largest of the swing states anchors the Sun Belt, the band of states across the US South and Southwest that is rapidly growing in population, and features agriculture and military industry and large numbers of retirees.

Republicans are mounting a fierce defense here, with Democrats accusing them of actively suppressing the vote, particularly in communities of color.

The state’s huge Latino population will be key, and polls show them aligned with the Democratic ticket less than in 2016.

Most experts say Florida is a Trump firewall; if it’s breached, Trump likely loses the White House.

RCP: Biden by 1.8

North Carolina

This traditionally conservative state went to Trump by three percentage points four years ago but both parties acknowledge it is now too close to call.

North Carolina’s governor is a popular Democrat who has won praise for his balanced response to the pandemic.

Republicans based their national convention here last month, although it was largely online, and Trump was returning for his third visit in two weeks to the state that has already begun sending out its mail-in ballots.

RCP: Biden by 0.6

Arizona

Arizona has been a Republican stronghold for decades, but its electorate is changing, with a growing Latino community and an influx of more liberal Californians.

Conservative voters appreciate Trump’s efforts to restrict immigration and build a wall on the border with Mexico.

But Trump has hurt his prospects by repeatedly denigrating the late senator John McCain, who represented Arizona for decades in Washington and still looms large over the state’s politics.

RCP: Biden by 5.0