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. She 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, a handful of swing states will ?probably decide the election and be targeted heavily by campaigners.
Each day, the Guardian’s poll tracker takes a rolling 14-day average of the polls in ?eight swing states.