Former US Secretary of State Condoleezza Rice said the Republican Party must adapt rapidly changing demographics in the United States to remain politically relevant.
In a speech to the Democratic Party’s national convention, former President Bill Clinton appealed to millions of hard-pressed Americans to support the President Barack Obama for a second term in the White House.
The 5.500 Democrat delegates launched a vigorous defence of President Barack Obama on Tuesday and urged voters to give him another term to fix the economy as they opened their national convention with sharp criticism of Republican hopeful Mitt Romney.
Mitt Romney has pledged to restore the promise of America, as he accepted the Republican presidential nomination at the party's convention in Florida. The former Massachusetts governor accused President Barack Obama of failing to deliver on his soaring promises of hope and change. Mr Romney will challenge the Democratic president in November's election.
Republicans formally nominated Mitt Romney to challenge President Barack Obama for the White House, kicking off their storm-delayed convention with a barrage of sharp attacks on Obama's economic leadership.
Instead of opening with a bang as originally planned, Mitt Romney's Republican convention started with a whimper on Monday as party leaders staged a low-key session while Tropical Storm Isaac churned through the Gulf of Mexico.
Mitt Romney clinched the US Republican presidential nomination on Tuesday with a resounding victory in Texas and now faces a five-month sprint to convince voters to trust him over Democratic President Barack Obama in the November 6 election.
President Barack Obama, seizing on a report that showed the US rich getting richer while the rest of the country struggled to get ahead, said that Republicans were thwarting a fairer approach.
A record-high 81% of US citizens are dissatisfied with the way the country is being governed, adding to negativity that has been building over the past 10 years.
US President Barack Obama has been dealt a double setback after Republican wins in two seats, including one billed as a referendum on his economic policies. In New York, Republican Bob Turner won a key election to succeed Democratic Congressman Anthony Weiner, who quit in June over a sex texting scandal.