A recent poll shows 45 per cent of respondents consider Joe Biden to have the greatest chance of defeating Donald Trump. Candidates at Thursday's debate had a heated discussion about healthcare in the first 40 minutes of the debate, several stressed the importance of standing together as Democrats, saying fighting one another would play into Trump's hands.

US Democratic debate: front-runners vie for chance to defeat Donald Trump

A recent poll shows 45 per cent of respondents consider Joe Biden to have the greatest chance of defeating Donald Trump. Candidates at Thursday's debate had a heated discussion about healthcare in the first 40 minutes of the debate, several stressed the importance of standing together as Democrats, saying fighting one another would play into Trump's hands.