US senate leaders are racing against the clock to reach an agreement before the country's borrowing authority runs out next week.
In a move that could prove crucial in defining his second term, Obama has urged US Congress to extend a tax cut for middle class Americans.
The Romney campaign has confirmed that US presidential hopeful Mitt Romney has officially chosen Paul Ryan to be his running mate.
Republican candidates are gearing up for party nominations after Newt Gingrich's sensational victory in South Carolina threw the race wide open.
Michele Bachmann has ended her bid to become the Republican presidential nominee and called on supporters to rally behind the party's eventual choice.
Barack Obama has blasted his foes and Wall Street, portraying himself as a champion of the middle class and laying out themes of his re-election bid.
Barack Obama is to send thousands of campaign volunteers across the US in an effort to create one of the most sophisticated political operations.