Joe Biden is leading ​Donald Trump in the national polls for the presidential election, but that doesn’t guarantee ​the Democratic candidate victory. Hillary Clinton also had a clear lead over Trump in the polls for almost the entire 2016 campaign and ended up losing in the electoral college.

​Because the presidential ​voting system assigns each state a number of electoral college votes, which​ go to the state’s victor regardless of the​ margin of victory (with the exception of Nebraska and Maine), a handful of swing states will ​probably decide the election and be targeted heavily by campaigners.

The Guardian’s Lauren Gambino examines how the race is developing in the areas that could decide the election

• Watch Anywhere but Washington - our video series examining the key election battlegrounds

Although polling averages gave Clinton the edge over Trump in 2016 there are significant differences in the evidence today

For months, activists and Democratic party officials have been telling Joe Biden supporters that the only answer to the question “can we trust the polls?” is to go out and vote for Biden, and then get others to do the same.

Data from the US Elections Project predicts a record 150m ballots, representing 65% of eligible voters, for this election

More than 50 million Americans have cast ballots in the US presidential election with 11 days to go in the campaign, a pace that could lead to the highest voter turnout in over a century, according to data from the US Elections Project on Friday.

The eye-popping figure is a sign of intense interest in the contest between Republican Donald Trump and Joe Biden, his Democratic challenger, as well as Americans’ desire to reduce their risk of exposure to Covid-19, which has killed more than 221,000 people across the United States.

Trump tried to change his tone, Biden calls the president a racist and ‘Bidencare’ is now a thing

In the days leading up to the debate, Donald Trump’s advisers urged the president to stay calmer than he was at the first presidential debate in Cleveland last month, when he was widely criticized for repeatedly and aggressively interrupting his Democratic presidential rival, Joe Biden.