Nick Clegg began the year untouched by fame, just another Lib Dem leader who could walk the streets unmolested by passers-by.
In the general election TV debates, he burst into public consciousness, riding a wave of Cleggmania until - at least - the moment votes were actually cast.
He ended the year being cursed by thousands of students, burnt in effigy in Whitehall and having poo shoved through his front door.
From "Which Nick?" to "Saint Nick" to "Nasty Nick" in 12 months: truly a political rollercoaster. Who could blame him for wanting to get away and spend Christmas with his in-laws in Spain?
The puzzling thing though is that, in political terms, he has played his cards quite well.
He recognised immediately that he could secure more of his party's priorities in a formal coalition with the Conservatives.
He won a pupil premium, a referendum on electoral reform, more community sentences, the tax-free allowance raised to £10,000, and a delay to both inheritance tax cuts and the renewal of Trident nuclear weapons.
In return, he accepted the scale and speed of the Conservatives' spending cuts, a move that may be unpopular with some Lib Dems but allows him to argue that his party can be economically credible and politically responsible.
But then he decided to support a rise in tuition fees, something he had opposed in opposition.
His parliamentary party split, his ministers agonised, and students cried betrayal, taking to the streets to protest. Some demonstrators even attacked the police. No longer did people say: "I agree with Nick."
Some say that this is Mr Clegg's Iraq, the moment when a man who promised a new politics lost the trust of voters, never to be recovered.
Others say it will all be forgotten by the general election in four years' time, and that his political bottle will be remembered as much as his policy betrayal.
Inevitably, there is a joke.
A man rings up the Lib Dems for a copy of their manifesto.
"We've sold out," comes the reply.
"Yes, I know that," the man says. "I just want a manifesto."
One reason why Mr Clegg stood firm over tuition fees was his desire to prove that the Lib Dems could be a serious party of government, one that could take tough decisions and stand by them.
One whose ministers were tough, competent and steadfast.
The irony is that all that work was undone by Business Secretary Vince Cable and other ministers' loose talk to the Daily Telegraph's undercover reporters.
This showed an ill-discipline and naivety that will make it harder for the deputy prime minister to argue that his party is fit to govern.
It will also make it easier for critics to claim that Lib Dems say different things to different audiences.
Mr Clegg's aim over the next year is to keep his parliamentary party together, to ensure that the split over tuition fees does not become a permanent fissure, an historic break between the party's leftish social democrats and their more centrist liberals.
So he needs some early victories in the new year, such as abolishing control orders, curbing executive pay and progress towards an elected House of Lords.
He needs to show voters that he and his party are shaping the government's priorities.
And, despite opinion poll ratings in single figures, he needs to do well in next year's elections: not only the Oldham East and Saddleworth by-election in early January, but also elections for local councils and the devolved assemblies in May.
There is also the small matter of trying to win a referendum on the alternative vote, which on current projections looks a big ask.
Mr Clegg's hope is that for all the flak he is getting, as the months pass, voters will see the Lib Dems moving from being a party of protest to one of power, showing that coalition politics works.
The danger is that he remains a human shield for David Cameron, a junior coalition partner doomed never to benefit from any economic recovery.
Mr Clegg has - by all accounts - stayed cool under fire this year. But when asked on Desert Island Discs what his luxury would be, there is a reason he chose a stash of cigarettes.