Not me, not Bill, no one more qualified than Hillary to lead US: Obama

President Barack Obama painted an optimistic picture of America's future in a speech aimed at giving full-hearted support to Hillary Clinton to help her defeat Republican rival Donald Trump and become the first woman elected US president.

"There has never been a man or woman, not me, not Bill (Clinton) - nobody more qualified than Hillary Clinton to serve as president of the United States," Obama said to cheers.

Speaking to the Democratic Party convention in Philadelphia, Obama offered an alternative to businessman Trump's vision of the United States as being under siege from illegal immigrants and terrorism and losing its way in the world.

"I am more optimistic about the future of America than ever before," Obama told cheering delegates at the Wells Fargo Center.

The Democratic president laid out what he said were a series of advances during his two terms in office, such as recovery from economic recession, the Obamacare healthcare reform and the 2011 killing of Al Qaeda leader Osama bin Laden.

Nodding to voters' concerns, Obama said he understood frustrations "with political gridlock, worry about racial divisions" and the slow pace of economic growth.

"There are pockets of America that never recovered from factory closures; men who took pride in hard work and providing for their families who now feel forgotten," Obama said.

HERE IS WHAT HE SAID:

- Hillary's strength is her unbelievable work ethic.
- The America I know is decent and generous, we have created history.
- America's promises don't come with a price tag.
- In midst of crisis, Hillary keeps her cool. She has real plans to break down barriers.
- Hillary knows that we can work through the racial divide in this country.
- The democracy doesn't work if we constantly demonise each other.
- We all need to get out and vote for democrats and hold them accountable until they get the job done.
- Democracy deosn't work during the election time, it works all year long.
- There has never been a man or woman, not me, not Bill, more qualified than Hilary to serve as US President.
- No matter how much people try to knock her down,Hillary Clinton never, ever quits,that's the Hilary I know.
- Donald Trump calls US military a disaster. He doesn't know men and women who make up strongest fighting force in World.
- No matter how much people try to knock her down,Hillary Clinton never, ever quits,that's the Hilary I know.
- Obama says 'deeply pessimistic vision' of America at GOP convention is 'not the America I know'
- Obama says he's "more optimistic about the future of America than ever before."
- The president says the nation has been tested by war and recession but he's more optimistic about the country's future.

- With inputs from AP and Reuters