Ms Buckell is standing on the ticket of the Campaign for Free Education, a group that has been described by Labour's Millbank headquarters as a "front organisation" for various far-left factions. The 25-year-old former Lancaster University student, came within 15 votes of winning the presidency from Labour last year, but is expected to beat Labour's Andrew Pakes this year.
In a sign that the Labour Party nationally is nervous of a left-wing victory, party officials have begun briefing against Ms Buckell in recent days.
In her manifesto, Ms Buckell states that she wants "a strategy of direct action and non-payment" to smash the Government's system of forcing students to take out loans for tuition fees. The Campaign for Free Education has so far organised sit-ins and occupations in several colleges and universities across the country and Labour sources claim that it is intent on a campaign of disruption of campuses.
A Millbank source said: "This woman is a danger to the future of the NUS because it will lose all credibility if it lurches to the left, like trade unions in the Eighties."
However, Mick Duncan, of the CFE, said that Ms Buckell's election would be a "disaster" for Labour and a boost for most students, who had endured 16 years of the party's acquiescence to cuts in student grants. "It would be a disaster for Tony Blair and David Blunkett who would have students accept tuition fees. Students are sick of years of cuts," he said.