The Week in Politics: Chancellor's ally plans to give Mr Blair an unhappy new year

Who is the most influential Labour MP at the close of a turbulent year in politics? Tony Blair? Gordon Brown? No. I reckon the winner is a former cabinet minister sacked by Mr Blair who remains close to the Chancellor.

It is Nick Brown, a former chief whip who is described by Blairites as the Chancellor's unofficial chief whip on the back benches. He matters because he is organising the rebellion against plans to allow universities to charge up to £3,000 a year in top-up fees, a revolt which could inflict a humiliating defeat on the Prime Minister at the end of next month.

Even Nick Brown's enemies do not doubt his brilliant organising skills. "Nobody knows Labour MPs better than Nick," one colleague said. "He knows what makes every one of them tick, about their concerns, their priorities, their constituencies, and so he knows precisely which arguments to deploy with them." At a time when Mr Blair needs all the friends he can get, he faces a dangerous enemy.

Mr Brown was one of the early, unsung heroes of the New Labour project. It is often forgotten that the rise up the ladder of Mr Blair and Gordon Brown was due to his skilful organisation, which got them elected to Neil Kinnock's shadow cabinet.

As MP for a Newcastle seat, Nick Brown was seen as a member of the "North-east mafia" around Mr Blair. Yet he has always been closer to the Chancellor. It is widely assumed that if Mr Brown becomes Prime Minister, he would restore his namesake to his rightful place in the whips' office.

Nick Brown had an unconventional ministerial career. He was made Chief Whip in 1997, but ousted the following year because the Blairites suspected his first loyalty was to the Chancellor rather than the Prime Minister. But his close links with Gordon Brown meant that Mr Blair felt unable to sack him from his government.

So he was promoted to the Cabinet, albeit to the lowly post of Agriculture Minister, where he had to cope with the outbreak of foot-and-mouth disease. His department's lacklustre performance angered Downing Street, which took revenge by merging it into a new Department of the Environment, Food and Rural Affairs.

When Mr Blair decided to remove Mr Brown from the Cabinet, Gordon Brown's intervention ensured that he was made Minister for Work, with special permission to attend cabinet meetings. He made little impact in this job and his civil servants noted acidly: "The Minister for Work doesn't really do very much."

Nick Brown was finally dropped from the Government in June, although Mr Blair saw fit to replace him as Minister for Work with Des Browne. You guessed it: with a name like that, he is another acolyte of Gordon Brown. The Chancellor's allies professed to be relaxed about Nick Brown's departure, with some noting that he would have more time to "organise for Gordon" on the back benches.

Which brings us back to top-up fees. The Chancellor's allies deny he is orchestrating the rebellion through Nick Brown. Indeed, in a recent interview, he said he had told Nick Brown to support the Government.

All the same, Labour MPs have little doubt that Nick Brown is articulating in public his namesake's private doubts about variable top-up fees. "Gordon knew all along that this would be an Exocet missile aimed at the middle classes. Now this has finally dawned on the Blairites," one ally of the Chancellor said. Nick Brown has also highlighted the Chancellor's fears that fees will deter students from poor families from going to university.

After the usual grumbling from the Blairites, Gordon Brown rallied behind the policy, while making it clear that variable fees, "the biggest gripe of the Labour rebels", were Mr Blair's personal decision. The Chancellor offered to help draw up a repayment scheme that Labour MPs could accept, though in private he is driving a hard bargain with Charles Clarke, the Secretary of State for Education. "Gordon is not prepared to stump up extra money," one aide said.

When Nick Brown left Westminster for his Christmas break, I am told, he was convinced that 100 of the 157 rebels would stand firm and vote against the Higher Education Bill, more than enough to defeat Mr Blair. In an attempt to defuse the revolt, some changes will be announced by Mr Clarke when the Commons resumes on 5 January.

The Government should be able to avoid defeat by dribbling out more concessions in the run-up to the vote. But all the signs are that Mr Blair will not give way on the critical element - allowing variable fees to be charged by different universities and for different courses. "We saw the Bill on foundation hospitals neutered by salami-slicing; we are not prepared to do the same on tuition fees," one Blair aide told me.

If Mr Blair loses, it will be sweet revenge for Nick Brown over his sacking: the organising skills which once helped the Prime Minister will have delivered a wounding blow to his authority. If Mr Blair wins, then Mr Brown will take comfort from the perception that the Chancellor's intervention will have saved the Prime Minister from defeat. So he starts the new year on a good each-way bet.

The hypertension in Downing Street was illustrated just before Christmas when officials tipped off broadcasters that a big story was about to break. They could not say it was Libya's decision to give up its weapons of mass destruction because the details were still being bolted down. But off their own bat officials reassured the BBC that the Prime Minister was not resigning. This would not have happened a few months ago and, for Mr Blair, is a pretty gloomy sign of the times.

a.grice@independent.co.uk