Tim Russert: Influential political journalist

Officially, Hillary Clinton did not concede defeat in her presidential bid until 7 June. In fact, the obituary that mattered had been pronounced exactly a month earlier. "We now know who the [Democratic] nominee will be, and no-one's going to dispute it," Tim Russert, NBC News' top political commentator, declared on the night of her stinging defeat by Barack Obama in the North Carolina primary – and she might as well have thrown in the towel there and then.

Russert's remarks, and their treatment by the rest of the media as a news story in its own right, merely underlined his status as perhaps his country's most influential political journalist. His podium was NBC's Meet the Press, the fusty old current affairs progamme which Russert took over in 1991 and quickly turned into the most entertaining and most important of the competing Sunday morning talk shows.

Russert was a bear of a man, genial and gregarious, who loved the political game. If he had a fault, it might be said that, like the rest of his trade, he was too close to the people he covered, in a journalistic culture notably more deferential towards politicians than Britain's.

In fact, he was among the toughest interviewers on American television. His technique was a forensic style of interrogation, probably deriving from his training as a lawyer. It was based on doing his homework, combing his subject's record, ferreting out his or her inconsistencies and changes in position, and zeroing in on those contradictions, live on TV.

As a result, a grilling on Meet the Press became a rite of passage for politicians and top government officials, and for presidential candidates in particular. A strong performance could give a major boost, while a weak one, while it alone might not break a candidate, could deal a serious setback.

Though a consummate Washington insider, Russert delighted in displaying his Catholic working-class ancestry. His father was a one-time garbage worker in gritty blue-collar Buffalo in upstate New York, right on the border with Canada, who featured in Russert's bestselling father-son memoir of 2004, Big Russ & Me. During the NFL season, an edition of Meet the Press rarely passed without Russert mentioning his beloved Buffalo Bills football team.

After putting himself through law school, Tim Russert moved into politics, becoming chief of staff for Senator Patrick Daniel Moynihan in 1979 at the age of just 29. He then worked for Governor Mario Cuomo, another of New York state's class Democratic acts of the era, before moving into television.

Russert joined NBC in 1985, first as an assistant to the president of the network's news division, and then from 1988 as its Washington Bureau chief. Three years later he took over the venerable but dreary Meet the Press, transforming what was then a stale forum for newsmakers from the previous week into the top-rated Sunday talk show, earning NBC a reputed $50m a year in annual profits when Russert died, cut down by a heart attack as he was taping voice-overs for the show.

Among the highlights of his 17 years at its helm were long interviews with presidents, as well as several apppearances by Dick Cheney, including one just after the 9/11 attacks in which the vice-president gave a riveting inside account of events at the White House that day.

Later, Russert would play a part in the downfall of Cheney's top aide, Lewis "Scooter" Libby when the latter went on trial for leaking of the name of a CIA operative, Valerie Plame. Libby claimed to have learnt her name from Russert, but on the witness stand the journalist flatly denied it. In the end the jury believed Russert, not Libby, who was convicted of perjury in the affair.

Rupert Cornwell

Timothy John Russert, journalist: born Buffalo, New York 7 May 1950; married 1983 Maureen Orth (one son); died Washington, DC, 13 June 2008.