It was undoubtedly partly a personal vote for Douglas Carswell. It would not happen in a general election. But that does not mean that Ukip’s success in Clacton – and its near victory in Heywood and Middleton - do not matter.
For a start, even by the standards of previous by-elections the Ukip’s performance in both seats was quite remarkable. In winning nearly 60 per cent of the vote from a standing start, Mr Carswell secured the biggest increase in support ever recorded by a by-election candidate, outpacing the 53-point increase secured by George Galloway in Bradford West two years ago.
Meanwhile, not only was the 39 per cent share that Ukip won in Heywood and Middleton well above anything the party had ever managed to win in a by-election before Thursday, but the 36-point increase in support it represented is itself one of the biggest surges ever recorded in a by-election. Only in six previous contests on the UK mainland has a party added more votes to its tally than Ukip managed in Heywood.
But more important are the likely knock-on consequences of these performances. Both the Conservatives and Labour have been praying that the Ukip bubble – currently averaging 13 per cent in the opinion polls - will deflate as the general election approaches, and voters start thinking about who they would like to govern the country for the next five years.
However, Ukip now has the oxygen of further electoral success to help it sustain its support through to next May. Moreover, the claim that a vote for Ukip is a wasted vote or will let Ed Miliband in can now be met with the riposte that in fact a vote for Ukip is a vote for a Ukip MP.
That will make both parties nervous about their prospects next May. But it will worry the Conservatives more. Although Ukip is undoubtedly taking votes from all parties, the polls still suggest that Nigel Farage is winning over more ex-Tories than ex-Labour supporters - and there is nothing in the pattern of Thursday’s results to contradict that evidence.
In pictures: The rise of Ukip
In pictures: The rise of Ukip
1/8 1993: Alan Sked forms Ukip
History professor Alan Sked had been active in anti-EU politics for a while beore he founded Ukip in 1993. He resigned from the party after the 1997 election, concerned that it was attracting far-right members, and has been critical of Ukip since. Picture: Reuters
2/8 2005: Kilroy defects
Former TV presenter Robert Kilroy-Silk founded Veritas in 2005, after a failed bid to become leader, and took many of Ukip's elected members with him. But the party slowly lost its popularity and didn't put forward any candidates in the last election. Picture: REUTERS/Kieran Doherty REUTERS KD/RUS
3/8 2010: Farage becomes leader, again
Farage had led Ukip from 2006 until 2009, when he stood down to fight against the Speaker, John Bercow, for his Buckingham seat. He failed to win the election and returned to lead the party in November 2010. Picture: REUTERS/Kieran Doherty
4/8 2010: Ukip fights for election
Nigel Farage was injured in a plane crash on polling day in the 2010 general election, but his party increased its success in the votes. It fielded 572 candidates and took 3.1% of the vote, though failed to win any seats. REUTERS/Darren Staples
5/8 2013: Eastleigh gains
Ukip's candidate Diane James got the highest ever number of votes for any candidate from the party, but was beaten by the Liberal Democrats. The surge in support gave Ukip confidence ahead of local and European elections later in the year. Picture: Reuters
6/8 2013: Bloom kicked out
Godfrey Bloom, who served as an Ukip MEP from 2004 to 2014, had the whip withdrawn in 2013 after sexist comments and an attack on a journalist. He sat as an independent MEP until 2014, when he ended his term in office. Picture: REUTERS/Luke MacGregor
7/8 2014: European election success
Ukip got a higher proportion of the vote than any other party in 2014's European elections, adding 11 new MEPs and taking its total to 24. REUTERS/Luke MacGregor
8/8 2014: Carswell defects
Douglas Carswell defected from Ukip at the end of August, and was followed by Mark Reckless at the end of September, who resigned from the Tories amid rumours of many more defections to come. Picture: REUTERS/Toby Melville
Yet there is little sign that voters are keen to see Labour back in government. In Heywood the party managed to add just one point to an already low share of the vote, while in Clacton its support was well and truly squeezed. Mr Miliband, it seems, is limping rather than leaping to power.
John Curtice is Professor of Politics, Strathclyde UniversityReuse content