Eliot Spitzer’s spectacular fall from grace abruptly ends what had been the meteoric rise of a politician with national ambitions - and also a major supporter of Hillary Clinton in her nomination battle against Barack Obama.

In the short term, the scandal will likely dominate the front pages and eclipse, at least for a day or two, the intensifying battle between Mrs Clinton and Mr Obama, at a time when the Illinois senator in particular was hoping to repair the damage inflicted on his campaign after his twin defeats in Ohio and Texas.

The scandal also encumbers the Democratic party with a high-profile episode of sleaze during a period of US politics when Republicans appeared to have almost a monopoly on such behaviour, from Senator Larry Craig’s gay airport lavatory sting to Jack Abramoff’s fraudulent lobbying activities.

One glaring exception to this, however, was the disgrace of Jim McGreevey, another married Democratic governor in the neighbouring state of New Jersey who was forced to resign in 2004 after being forced to admit that he had an affair with a male staffer.

Because Mr Spitzer is one of Mrs Clinton’s most powerful backers in her home state of New York, the former First Lady will inevitably be forced to comment on his behaviour, a distraction at a time when she has been mounting an effective comeback against Mr Obama after his string of victories in February.

In the long term, however, Mr Spitzer’s disgrace should have minimal impact on both the race for the Democratic nomination and the general election in the autumn. New York has already held its primary, on February 5, and the state sits firmly in the Democratic column when it comes to the main White House contest in November.

The bombshell revelations about Mr Spitzer were all the more startling because he had spent his life portraying himself as a paragon of virtue and moral rectitude, and as a federal prosecutor a scourge of Wall Street corruption. He won his landslide victory to become New York governor in 2006 after eight years as the state’s attorney-general.

His governership had encountered political problems in recent months, including an unpopular plan to grant drivers licenses to illegal immigrants and allegations that his aides had attempted to use police records to smear Republican opponents. Yet until yesterday, he was still being talked of as a potential presidential candidate.

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