Ferraro latest casualty in Democrat campaign

How many more aides will the rival Democratic candidates have to shed in the race for the US presidential nomination? The latest high-profile departure - the resignation on Wednesday of Geraldine Ferraro from the Hillary Clinton campaign - brings the number to three so far.

Ferraro stepped down from Clinton's fundraising committee after making ill-judged comments about Barack Obama's race that were subsequently disowned by Clinton. Obama, Ferraro said, was only ahead in the race because he was black.

She follows in the footsteps of Patti Sollis Doyle, who was relieved of her position as Hillary's campaign manager in February following a series of poor primary results.

Obama's team has suffered too. Samantha Power, an Irish-born scholar who was working as a foreign policy aide to the Illinois senator, was cut loose last week. Power had described Hillary Clinton as a "monster" in an off-the-record comment to a reporter with the Scotsman newspaper, who subsequently printed the remark.

With a six-week gap until the Pennsylvania primary on April 22, there's sure to be the opportunity for more gaffes. Though none are likely to come from someone so senior in the Democratic party as Ferraro who might have been the United States’ first women vice-president a quarter-century before Clinton attempted to run for president. She was chosen by Walter Mondale as his running-mate in 1984 to popular acclaim - but they were thrashed at the November election by Ronald Reagan and George Bush Sr.