Jason Rae is a 21-year-old student and has never voted in a presidential election. Now he is set to play an oversized role in determining whether Barack Obama or Hillary Clinton is the Democratic nominee this year.

As an elected member of the Democratic National Committee, Mr Rae is part of the elite club of 795 so-called super-delegates who may finally tip the balance at the presidential convention in August.

Between his history and political science classes at Marquette University in Wisconsin, Mr Rae’s phone rings hot with calls from people whom he might otherwise have been studying but are now desperate for his endorsement.

One began with the words: “Hey, Jason, it’s Bill here.” That was Bill as in Clinton, the former President, who explained why his wife was more likely to win back the White House and then regaled him lengthily with stories about past campaigns.

Mr Rae has received numerous other calls on behalf of Mrs Clinton, including one from Madeleine Albright, the former Secretary of State.

On Monday it was the turn of Chelsea Clinton, who arrived in person to have breakfast with him in a student canteen.

“It was not that glamourous,” Mr Rae admitted yesterday. He had a banana and drank apple juice but cannot remember what Ms Clinton ate. They discussed how to get young people involved in politics and the states that her mother can win. “She’s an extremely sweet girl,” he said.

Nor have Mr Obama’s backers been shy of lobbying Mr Rae. At the beginning of the month he received a call from John Kerry, the Democratic nominee in 2004, who softened him up with some chat about campus life and the weather as he pressed his favoured candidate’s claims to electability.

Such episodes are a reflection of the prospect that neither Mrs Clinton nor the surging Mr Obama may get the 2,025 delegates needed for nomination without focusing — lavishing even — unprecedented attention on the likes of Mr Rae.

If Mr Obama pulls off a win in Ohio and Texas on March 4, then superdelegates are likely to stampede over to his campaign.

Even if he loses, his aides say that he has amassed an advantage of more than 100 elected delegates which will be “next to impossible” for Mrs Clinton to claw back before the convention.

Mrs Clinton believes that superdelegates, among whom she still has the edge, can tip the nomination her way if she halts her rival’s momentum by winning the big states next month.

Mr Obama’s camp is warning the party leadership not to frustrate the will of voters by picking a candidate who has fewer votes and delegates than him.

David Wilhelm, Mr Clinton’s 1992 campaign manager, has announced that he is voting for Mr Obama partly to “even up the disproportionate share of super-delegates backing Hillary”.

Nancy Pelosi, the House of Representatives Speaker, has suggested that they will “be sensitive to the public will”.

Mark Penn, Mrs Clinton’s chief strategist, makes a different argument. He says that super-delegates should base their decision on “where the win comes from” in November — when one of the candidates will face John McCain.

Indeed, there are signs that as the Democrats fight it out, the Republicans may at last be getting their act together. Last night Mitt Romney endorsed his one-time rival Mr Mc Cain, demonstrating a much-needed show of Republican unity.

Both Democrats insist that they are best placed to beat Mr McCain. Mr Obama’s credentials for reaching out across party lines was boosted yesterday by an endorsement from Lincoln Chafee, the former Republican senator for Rhode Island. Mrs Clinton, meanwhile, is honing a new message of economic populism and sharpening her attacks on Mr Obama, telling a crowd in Ohio yesterday that his speeches getting “people excited” about change was not the same as offering real progress.

Yesterday she was declared the winner by a tiny margin in New Mexico, which held its elections on Super Tuesday eight days ago but last night gave the Clinton campaign a much-needed fillip.

Back in Wisconsin, Mr Rae remains undecided, even as his own state’s primary looms on Tuesday.

“I don’t know in my heart of hearts who I want. As of right now I’m not planning to endorse but, of course, in politics things can change very quickly,” he said, sounding like one of those hard-boiled convention operatives of old.

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