As Conservatives watched their working majority cut to one in the Brecon and Radnorshire byelection on Friday morning, they consoled themselves with the knowledge that it could have been worse. The Liberal Democrats were runaway favourites to win the seat and their majority of 1,425 was at the lower end of expectations.
The "Boris bounce" seen in national polls since Boris Johnson became prime minister last week was not enough for the Conservatives to hold the seat but it helped to push the Brexit Party's vote share down to 10.5 per cent. And Labour had a terrible night, almost losing their deposit as they came in fourth with just 1,680 votes.
The defeat creates a headache for Johnson, however, not only in terms of parliamentary arithmetic but for his prospects of winning a snap general election in the autumn. Nigel Farage's Brexit Party has shown that it can deny Conservatives victory by splitting the Leave vote. And the Liberal Democrats' successful electoral pact with the Greens and Plaid Cymru could be replicated across the country in a general election.
Tactical vote
Labour has not held Brecon and Radnorshire since 1979 and its vote was always likely to be squeezed in a two-way contest. But while its fourth-place showing should worry Jeremy Corbyn, it testifies to the fact that Labour supporters are again willing to vote tactically for the Liberal Democrats, who were long tainted for many on the left by their coalition with David Cameron's Conservatives.
Most of the Liberal Democrats’ target seats for a general election are held by Conservatives, so their resurgence is a bigger threat to Johnson than to Corbyn. But Johnson has no hope of winning a Commons majority unless he crushes the Brexit Party.
Farage's party this week announced 150 new candidates for the general election and, in a message to supporters on Friday, party chairman Richard Tice took aim at the new prime minister.
Vassal state
“It appears that Tory leader Boris Johnson is now moving towards a reheated version of Theresa May’s terrible withdrawal agreement – the worst deal in history, a treaty that was accurately described by Boris as reducing the UK to a state of ‘vassalage’,” he said.
“As you would expect, exposing Boris’ backsliding on Brexit will be a focus for us in the weeks ahead.”
To see off the Brexit Party, Johnson must maintain his hardline stance on Brexit, a course likely to drive moderate Conservatives towards the resurgent Liberal Democrats in greater numbers.
If he cannot expect to win a general election before October 31st, Johnson will face a choice between agreeing a deal with the EU and the electorally hazardous options of postponing Brexit again or crashing out without a deal.