Pollsters may be wary of findings indicating unusually large leads for one candidate and introducing corrective weighting, experts say

Democrat Kamala Harris and Republican Donald Trump head to North Carolina on Saturday to try to clinch support in the south-eastern battleground state just three days before Tuesday’s US presidential election.

It will be the fourth day in a row that vice-president Harris and former president Trump visit the same state on the same day, underlining the critical importance of the seven states likely to decide the race, which opinion polls show to be on a knife’s edge, Reuters reported.