2012 US campaign may be most unpredictable yet

The 2012 race for the White House is shaping up to be the dirtiest yet.

The Republicans have gathered in Florida for their convention which will see Mitt Romney formally nominated to take on Barack Obama on November 6.

As momentum gathers, the rhetoric and advertising has become increasingly nasty.

Veteran newsman Dan Rather has been covering presidential elections since the mid-1950s.

Sky News reports Mr Rather says the 2012 election will be the first in which the Democrats and Republicans will spend a combined total of around three billion dollars.

He says it's a very unpredictable an volatile campaign.

"It's close, shaded a bit in Obama's favour at the moment. But put me on record as saying that there's a long way to go and Mitt Romney and the Republicans can win this election.

"And we've seen really dirty campaigns before but nothing compared to this one so far. This campaign already has been nasty enough to choke a buzzard."

And things haven't gone to plan for the Republicans in Florida.

The first day of the convention have been scrapped because of the threat posed by Tropical Storm Isaac.

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