It is the size of the vote for Reform UK that is probably causing the biggest headache for Prime Minister Rishi Sunak this morning.
The new right wing party has for the first time translated good showing in opinion polls into actual votes.
Mr Sunak may be worried that he could be literally outflanked.
In Kingswood in the West Country it won 10% of the vote which is the first time the party reached that level.
In Wellingborough in the East Midlands, the party got 13% which is a new record.
The difference between the two is reminiscent of the difference in the Brexit vote – which was 57% pro-leave in Kingswood but 63% in Wellingborough.
Reform UK was originally the Brexit Party and Nigel Farage is honorary president of the new party.
Political commentators are saying that Labour now has competition when it comes to picking up disaffected Tory voters.
But the Conservatives will be the most worried as the prospect of a new hard right party suddenly gaining momentum will hurt them more.
Reform UK’s policies mirror those of the new right wing populist parties in Europe – they want zero immigration, lower taxes and abandonment of net zero targets as a means of getting cheaper energy.
They also match the beliefs of hard right Tory backbenchers who have been unsuccessfully trying to organise rebellions in the Commons.
One figure that will concentrate No 10 strategists’ minds is the result in Wellingborough where the Reform UK candidate Ben Habib (who is the party’s deputy leader) got 3,919 votes compared to 7,408 for the Conservative candidate.
In other words the Reform UK vote is now up to 53% the size of the Tory vote.
One does not need a mathematician to work out what that would do to the Conservatives in a general election.
Jacob Rees-Mogg, whose constituency is in the West Country, said that the combined right wing vote would have won in Kingswood.
He seemed to be appealing for the voting arrangement that saw Reform UK stand aside in many constituencies and let Boris Johnson win his 80 seat majority in 2019.
However Reform UK leader Richard Tice has spoken of his disillusionment with the current government.
And he has vowed to contest every single constituency next time.
The Tories are blaming their by-election losses on the low turnout of 37% and 38%.
However as polling expert John Curtice has pointed out, the low turnout figures are a feature of all recent by-elections including those where the seat is held by Labour.
And Mr Curtice says even if it could be proved that the results were due to Tory voters staying at home, there is still no guarantee that they will turn out for the party in the next general election.
Conservatives suffer double blow as Labour win UK by-elections
