Former Texas Senator Phil Gramm has resigned from his role as Republican presidential candidate John McCain’s campaign co-chairman, hoping to quiet the uproar that followed his comments that Americans had become a “nation of whiners” whose constant complaints about the US economy show they are in a “mental recession”.

Barack Obama today appealed to American voters struggling with the skyrocketing price of petrol, casting Republican rival John McCain as a Washington insider who is in part responsible for the country’s dependence on foreign oil.