Trump failed to deliver any knockout blows in fractious presidential debate

US president Donald Trump: His combative and chaotic behavior during the presidential debate is unlikely to have swayed any undecided voters. Picture: Olivier Douliery/Pool vi AP)

Down in the opinion polls with five weeks to go until the November election, US president Donald Trump sought to use the first presidential debate to bully his way back into the race. Repeatedly interrupting and sparring with opponent Joe Biden, the Republican Trump tried to knock the Democratic former vice president off his feet Tuesday night and alter the dynamic of a contest he has been losing for months.

It was unlikely the president succeeded, largely because of his own combative and chaotic behaviour but also because the insult-filled and often fact-free affair may have left the few undecided voters watching at home more dispirited than engaged.