DENVER - MICHELLE Obama pledged to Americans and the world on Monday that her husband Barack Obama would be an 'extraordinary president' who would give all children the chance to fulfil their dreams.

Mrs Michelle Obama, 44, said in remarks released by her husband's campaign that she and her husband shared the values of heartland Americans, as she kicked off an attempt to flesh out the Democratic White House hopeful's biography.

Daddy's little girls win hearts TWO little girls stole the hearts of Democratic diehards here Monday as they appeared on stage blowing kisses to their daddy, Barack Obama, after a rousing speech by their mom. Malia, 10, and Sasha, seven, joined their mother, Michelle Obama, on a vast blue-carpeted stage after hearing her pledge to Americans and the world that their father would be an 'extraordinary president'. ... more

'I come here as a wife who loves my husband and believes he will be an extraordinary president,' said Mrs Obama in the remarks released ahead of her opening night keynote speech at the Democratic National convention here.

'I come here as a mum whose girls are the heart of my heart and the centre of my world,' said Mrs Obama, mother to two young daughters, Malia and Sasha.

'We want our children and all children in this nation, to know that the only limit to the height of your achievements is the reach of your dreams and your willingness to work for them.'

The passionate speech was to be delivered before some 4,400 delegates at the opening night of the Democratic Party convention set to nominate Mr Barack Obama, 47, as the country's first black presidential nominee.

It raises the curtain on a carefully choreographed four-day jamboree seeking to propel the Illinois senator forward into the final stretch of the 2008 presidential campaign and the November 4 elections.

'Nobody in the world knows Barack Obama better than his wife Michelle,' Obama spokesman Josh Earnest said earlier on Monday.

'Her personal perspective and what she offers will, I think, be very compelling to the American public.' Mr Barack Obama's half-sister Maya Soetero-Ng also took to the stage to praise her brother, who she said had introduced her 'mind and spirit to a broader world' and taught her 'about the importance of standing up for what you believe'.

She paid a moving tribute to their mother who 'encouraged us to explore, and ask questions and delight in unexpected discoveries and surprising answers'.

'She brought us to telescopes and microscopes to remind us that there was a world, a vast world beyond our limited reach,' Mrs Soetero-Ng said.

Despite the long, gruelling primary season which saw them fly coast to coast, north to south, some voters remain wary of Mr Barack Obama, the son of a Kenyan father and white Kansas mother, with an exotic name who spent his childhood in Indonesia and Hawaii.

Over the past months, Mrs Michelle Obama has shot to the fore in her husband's bid to wrest the White House from the Republicans.

She has criss-crossed the country appearing at meetings and rallies in a bid to help win over fans, especially women, to her husband's side. She has emerged as a charismatic, independent woman who has sought to build up her husband, while at the same time reminding everyone he is just an ordinary man.

She has swapped stories with voters and sympathised with everyday concerns such as the struggle to pay the bills, and to juggle work and family life. And she has candidly revealed that, like most couples, they have had their ups and downs.

Her simple, elegant style of dress, often topped with large colourful fake pearls, has turned her into a fashion icon for many.

Husband Barack has called her his rock, and one of the wisest people he knows.

But Mrs Michelle Obama will also have the job of selling herself, after she was attacked by the Republicans as unpatriotic for a badly-phrased quote in which she said that the wave of support for her husband had made her feel proud of her country for the first time.

Just hours before Mrs Michelle Obama's speech, Mrs Cindy McCain, wife of Republican presidential candidate John McCain, told Time.com that she was to visit Georgia on a World Food Program mission and meet President Mikheil Saakashvili.

Mrs McCain left on the trip on Monday, which will underscore the Republican White House hopeful's strong support for Georgia during its showdown with Russia. -- AFP