AMERICA: Democrat Joe Biden showed his boss how it was done in a successful performance at the US vice-presidential debate.

Vice President Biden expertly took his opportunity to hit out at the Republicans after a weak performance by President Barack Obama in his own debate last week.

Republicans however, criticised Biden as unprofessional and annoying for grinning sarcastically as his Republican rival Paul Ryan spoke.

All were surprised to see Biden emerge from the debate in Kentucky gaffe-free.

For Wisconsin congressman Ryan, this was a first widely televised debate. His composed speech hit on many familiar talking points and raised applause from a crowd watching on TV at a local restaurant.

Vice presidential debates rarely sway voters, but last night's event put pressure on Biden to help the Democrats rebound from presidential candidate Mitt Romney's surprisingly strong debate performance last week.

Joanne Harvey, a registered independent who voted for Obama in 2008, watched the debate at a bar viewing party organised by Republican presidential candidate Mitt Romney's campaign.

She said: "I don't think the debate will have much impact (on the votes). But I think Ryan showed he was more mature, smarter and more articulate than everyone thought he is."

It now sets up an exciting presidential debate next Tuesday, which could well be the most important event of the entire campaign.