Which swing states could decide the US election? – video explainer
Which swing states could decide the US election? – video explainer

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.