31 October 2011 Last updated at 19:30 ET

Article written by Mark Mardell North America editor

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Herman Cain: A 'high-tech lynching'?

 

Herman Cain unexpectedly bursts into song at the National Press Club

Never let it be said that Republican presidential hopeful Herman Cain lacks the ability to surprise.

US media were speculating about what he would say, hours before his appearance at the National Press Club. But no-one was expecting him to burst into song.

His rendition of a gospel hymn didn't overshadow the main business, however, and his response to the allegations made at the weekend were somewhat more conventional.

Just like a regular politician, in fact.

He told the National Press Club he wants to clear the air. He says he has never sexually harassed anyone.

Rebutting the allegations

But he admits there was an accusation of harassment made when he was in charge of the National Restaurant Association.

He says an internal investigation concluded there was no basis for the allegation.

Crucially, he says, he was not aware of any payment but did not firmly say there wasn't one.

The puzzle remains. If he was found to be innocent why would his employers make a payout?

If a payment was made, is it credible that the head of the organisation knew nothing about it?

Journalists will not stop digging until things are clearer.

It is an important moment for Mr Cain. Inside the Washington bubble, the businessman and former lobbyist is dismissed as a lightweight.

Outside the Beltway, conservatives love him and have put him at the top of several opinion polls.

But primary elections are a destruction derby and scandals can crush candidates.

Ann Coulter, a right-wing commentator, called the claims "another high-tech lynching", saying liberals couldn't stand strong black conservatives.

Her comments echoed the famous line by Clarence Thomas, a black US Supreme Court judge, denying sexual harassment allegations during his confirmation hearings in 1991.

Others think Cain's already finished because of the way he's handled the original story.

This could be an important moment for the whole Republican race.

Republican right-wingers dislike former Massachusetts Governor Mitt Romney, who is consistently in first or second place in the opinion polls and who most objective observers presume will, in the end, be the Republican choice.

The conservatives desperately want an alternative.

Yet, if they continue to give their love to one candidate for a short while before ditching them and alighting on a new favourite, then their vote will be split and Romney will sail through the middle.

If, however, a clear "anti-Mitt" candidate emerges head-and-shoulders above the rest, Romney could be in real trouble.

This is the moment when we see whether Cain can manage the pressure and whether his campaign team is up to rebutting the allegations.