Harris to face biggest test of her political life with Democratic convention speech

Democratic nominee, who has overturned Trump's poll lead, aims to persuade voters to back her vision for the US

Kamala Harris will tonight face the biggest test of her political life so far when she addresses the Democratic national convention in Chicago in a bid to persuade American voters to defeat Donald Trump in November's presidential election and put her in the White House.

The vice-president's rocket-fueled campaign is still barely a month old following Joe Biden's decision to withdraw from seeking re-election in the face of a disastrous debate performance and questions over his age and mental acuity.