The Lib Dems are targeting swathes of seats held by Conservatives at the next general election.

The anti-Brexit party led by Jo Swinson believes an election will happen this autumn.

Party figures and MPs tell Business Insider they are confident that the Tories' embrace of Boris Johnson and no-deal Brexit has driven their voters to the Lib Dems across a number of seats.

However, a Lib Dem resurgence could indirectly help Johnson and his mission to deliver Brexit.

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The Liberal Democrats are in a confident mood as they prepare for a possible snap general election.

The anti-Brexit party, now led by Jo Swinson, is buoyed by its resurgence in 2019. It surged in local and European Parliament elections earlier this year, and last week won the Brecon and Radnorshire by-election.

Some polls have put the Lib Dems close behind — or level with — the Conservatives and Labour.

Party figures are bullish about their prospects in an autumn election, which Boris Johnson is reportedly considering. They believe they pose a direct threat to the Conservatives, as Johnson tries to consume Brexit Party support with his "do or die" approach to leaving the European Union, and pushes the United Kingdom closer to a no-deal exit.

There is speculation that the Lib Dems will soon fire warning shots to the Tories by unveiling up to three new MPs.

Former Conservative MP Sarah Wollaston, who is now an independent, is set to be the first. The party has also had talks with current Conservative MP Philip Lee and ex-Tory Heidi Allen. Former minister Lee said last week he would "spend the summer" mulling whether to defect to the Lib Dems.

One party source said they have plans to unveil a new MP at their conference in Bournemouth next month.

Lib Dems plan to take the Conservative 'blue wall'

Aside from possible defections, the party has also set its sights on swathes of seats held by Conservative MPs. Party sources say the the number of seats they can take from the Tories at the next election is in double figures.

These seats — largely but not exclusively in the south of England — were part of the "blue wall" that was key to ex-prime minister David Cameron's majority victory at the 2015 general election. These target seats include Cheltenham and St Ives in the southwest, plus Richmond Park and St Albans in the southeast.

Repelled by the Conservative party's lurch to the right, its embrace of a no deal, and the election of Johnson as prime minister, "moderate" Tory voters in these seats are ready to ditch their old party for the Lib Dems, the latter says.

Sarah Olney, the Lib Dem candidate in Richmond Park, said many voters in her south London constituency were abandoning the Conservatives as they become the party of the hardest-possible Brexit.

"They really strongly believe the Conservatives no longer reflect their own political feelings — and these are people who always voted Tory," Olney – who served as the seat's MP for six months in 2017 — told Business Insider.

"What they believe in is stability and prosperity, and they don't feel they're getting that with the Conservatives."

Richmond Park is the Lib Dems' top target seat in England. They were just 45 votes behind the Tories there in 2017.

Sarah Olney, Lib Dem candidate in Richmond Park. Peter Nicholls/Reuters

Olney said a "fundamental" shift was happening on the ground, with voters who in 2017 were not prepared to ditch the Tories and risk a government led by Labour leader Jeremy Corbyn, now prepared to do so. "They still don't want a Corbyn government but nor do they want their votes to be used as a mandate for a no-deal Brexit," Olney said.

Daisy Cooper, the party's candidate in St Albans, just north of London, told Business Insider that the Conservative MP there "was out of touch on a whole range of issues and with their [constituents'] values."

The seat's MP is Anne Main, who belongs to the European Research Group of staunch pro-Brexit Conservative MPs. Estimates suggest the anti-Brexit Lib Dems won in St Albans with over 40% of the vote at the European elections.

Cooper said the Lib Dems could win in "upwards of 100 seats" in total at the next election. Both her and Olney said former Tories in their constituencies were not just repeatedly bringing up Brexit, but climate change and crime too.

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Chuka Umunna MP, the party's Treasury spokesperson, told Business Insider "either you seek to retain One Nation, Remain-orientated Tory voters, or you seek to take Brexit Party and Labour Leave support. You can't do both.

"It increasingly looks like — given the Vote Leave, ultra-hard Brexit complexion of the government — that the Conservatives are saying to Remain-voting, or even soft Brexit Tory voters, we are no longer interested in you."

"We [the Liberal Democrats] are quite clear as a party that the Lib Dems are the home for those voters."

A 'blessing in disguise' for Johnson?

Boris Johnson. Reuters

While Lib Dems are optimistic about taking seats from the Tories at the next election, they realise that eroding this particular constituency of the Conservatives' electoral coalition is not necessarily a route to stopping Brexit.

In fact, the Lib Dem resurgence, should it hold into the next election, could be a "blessing in disguise" for Johnson and his mission to deliver Brexit, according to Chris Curtis, a political researcher at YouGov.

He told Business Insider that while the Lib Dems were likely to win seats currently held by Tories at the next election, they could actually help Johnson indirectly, by taking votes from Labour in Conservative-Labour marginal seats.

YouGov's latest opinion poll put the Lib Dems on 21%, just one point behind Labour. Its recent research showed that for every one vote the Lib Dems were taking off the Conservatives, they were taking at least two off Labour.

"While the Tories could lose 20 or 30 seats on that flank [to the Lib Dems], if the Lib Dems take a lot of votes from Labour in Labour-Tory marginals, then the Conservatives can make up their losses to the Lib Dems," Curtis said.

Johnson feasibly could offset seats lost to Swinson with seats gained at the expense of the Labour Party bleeding pro-EU support to the Lib Dems. This means that contrary to some recent commentary, the Tories do not necessarily have to preserve Cameron's "blue wall" in order to win the next election and form a majority government.

This at least partly explains why Johnson, guided by political advisor Dominic Cummings, has prioritised winning the Brexit Party vote, which consists of many former Conservative voters. If he can unite Leavers behind him, the collapse of the Tories' "moderate" pillar at the expense of the Lib Dems, likely won't stop the Tories staying in government.

"As far as I can see, it's the best strategy they [the Conservatives] have got," YouGov's Curtis told Business Insider.

Jo Swinson. Dinendra Haria/SOPA Images/LightRocket via Getty Images

How can the Lib Dems and other Remain parties combat this?

One possible strategy that is being discussed is an electoral alliance involving Labour MPs in a handful of seats.

It is very unlikely that Labour HQ would approve a formal pact between their MPs and those from other parties. This is particularly the case for the Lib Dems, who Labour lambaste for their role in the Coaliton government.

However, writer Nick Cohen revealed yesterday that Unite to Remain — a cross-party, anti-Brexit alliance headed by Heidi Allen — would not actively campaign in seats where Labour MPs who clearly want to stop Brexit were standing.

Figures elsewhere in the pro-EU movement told Business Insider they've had positive discussions with a handful of Labour MPs who explicitly oppose Brexit, about coordinating with candidates from other Remain parties.

Moreover, the phenomenon described by YouGov's Curtis — in which a Lib Dem resurgence actually helps Prime Minister Johnson — will not materialise if Nigel Farage's Brexit Party enjoys a spike in support come election time.

Farage has said he does not trust the Tories enough to help by Johnson by standing down Brexit Party candidates in a snap election. Failure to deliver Brexit on October 31 could derail Johnson's momentum overnight.

What we know for sure is the Lib Dems pose a direct threat to a significant strand of Conservative support, and are well-placed to win several more House of Commons seats at the Tories' expense.

What's less clear is whether a successful Lib Dem assault on those target seats would help their mission to stop Brexit.