Dick Roche: So many factors still at play for candidates US election

The same factors that undermined Hillary Clinton’s polling advantage in 2016 still exist, and may be exaggerating Biden’s poll lead, writes Dick Roche

President Donald Trump and Democratic presidential candidate former Vice President Joe Biden participate in the final presidential debate last week. Picture: Jim Bourg/Pool via AP

When the final US presidential debate took place last Thursday, more than 50m Americans — one third of the expected turnout in the election — had already voted. The comparative figure at the same point in the 2016 presidential election was 5.9m votes cast.

A significant majority of early voters are registered Democrats. Republicans are expecting their voters to turn out on election day.