The Liberal Democrats have long been surging in areas that voted Remain. Tim Farron's party won the recent Richmond Park by-election by turning the contest into a referendum on Brexit. As the party of Remain, they stand to benefit from voters aggrieved by Theresa May's approach. An Ipsos MORI poll published yesterday put them on 14 per cent, their highest rating for five years. The party's membership has risen by 1,500 since their by-election victory.

But many have warned of the limitations of the "48 per cent strategy". While it served the Lib Dems well in Richmond (which was 72 per cent Remain) it could hinder them in Leave regions such as the south west. Only one of the party's top 30 Tory targets (Lewes) is a Remain seats with a Leave MP. But there is reason to believe the party can overcome this apparent hurdle.

In last night's council by-elections, the Lib Dems won two seats off the Tories in Teignbridge (which was 54 per cent Leave) and a seat off them in Taunton (53 per cent Leave), with dramatic swings in both cases. One should be wary of overinterpreting such contests, which are low turnout and local in nature. But the results suggest that there is potential for a Lib Dem recovery in both Remain and Leave areas.

In the aftermath of Richmond, Conservative MPs fretted that Farron's party could triumph by forging a pro-EU coalition of Labour and Green supporters. Under first-past-the-post, as the SNP can testify, seats can be won with significantly less than 50 per cent of the vote. If Remainers coalesce around the Lib Dems, while Leavers split between the Tories, Ukip and Labour, the former will benefit.

But it is also a mistake to treat voters as monolithic blocks. Brexiteers who want a strong, competent opposition to the Conservatives, and who value the Lib Dems' local approach, may be wooed back. As a former party strategist notes: "The parties' positions on Brexit won't be the only thing that is driving voter behaviour." Liberated from coalition, Farron's outfit is once again a vehicle for protest. For these reasons, it is not only in Remain seats that Tory anxiety is growing.