Joe Biden is likely to come under pressure to move swiftly on the free-college agenda, with data showing how his victory in the US presidential race was significantly aided by students and other young voters, but he faces serious political obstacles to driving through his flagship higher education policy.

Participation among voters aged 18 to 29 increased 8 per cent this year over the 2016 election, according to Tufts University researchers. And in an election with several critical state-wide tallies decided by slim margins, those young voters overwhelmingly favoured Mr Biden over Donald Trump, by a margin of 62 per cent to 35 per cent, according to exit polls.

Student participation may have proved decisive in some races: a surge in voting was reported around the University of Wisconsin-Madison, where the surrounding county gave Mr Biden a net gain of more than 180,000 votes in a key swing state that he appeared to have won by only about 20,000 votes.

That commitment was seen as being increasingly difficult to implement unless the Democrats could wrest control of the US Senate from Republicans. But their voting effort may now give students the power to insist that Mr Biden makes college costs a top priority in his overall policy negotiations with Republicans, said Paul Loeb, president of the Campus Election Engagement Project.

Details of the “pretty amazing” student vote tallies, on their own, probably won’t be enough to convince Mr Biden to fight an uphill political battle, said Mr Loeb, whose group works with universities to encourage student voting.

Instead, given the history of large year-to-year swings in young voter turnout, success on the overall free-college agenda would require sustained political engagement by students and their advocates throughout the administration, he said.

Mr Biden’s free-college plans looked unlikely to be implemented if the Republicans held the Senate, conceded Heather Gautney, an associate professor of sociology at Fordham University who advised the Biden campaign.

The two-year portion may enjoy enough bipartisan support to make progress at the federal level, especially given the number of states that have created such programmes, Dr Gautney said.

The four-year extension might be possible, she said, only if Mr Biden felt it important enough to engage in extensive negotiations involving trading priorities important to Republicans, such as defence spending.

“Everybody has a price,” Dr Gautney said. “I just don’t know where that lies on the hierarchy of priorities.”

The agenda may be assisted by Georgetown University research that found that the Biden proposals would pay for themselves in additional tax revenues within 10 years. Although it would initially cost $50 billion in state and federal revenue, and annual costs would reach $70 billion a year later, the added tax revenue from graduates earning higher incomes would begin overtaking and then rapidly exceeding the outlay, Georgetown researchers found

But in a nation with deep political divisions, said Tamara Hiler, the director of education policy at the thinktank Third Way, Mr Biden was not expected to push immediately on complicated issues such as free college.

“The Biden folks are not going to want to have free college the very first conversation that they are having,” Ms Hiler said.

The idea represented a potentially major expansion of taxpayer support for higher education by the federal government, which currently routes the bulk of such aid through money it provides to students.

This would aim to address the issue that while concerns over fees may be key in determining whether disadvantaged students enrol in university, if they do start, they are around four times less likely to complete their course than their more privileged classmates.

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