The Staggers 23 July 2019 Why Jo Swinson’s election may be a big problem for Boris Johnson The tide of voters turning to the Liberal Democrats could be just as profound a challenge for the Tories as the return of Farage. Getty Sign UpGet the New Statesman\'s Morning Call email. Sign-up Theresa May's successor as leader of the Conservative Party will be announced just before midday — but just how worried should they be about the result of this week's other leadership race? Jo Swinson has been elected the first woman leader of the Liberal Democrats, beating Ed Davey by a crushing margin of 63 per cent to 37 per cent. Boris Johnson will be hoping for a win of at least that scale over Jeremy Hunt, whose allies privately admit that anything above 35 per cent will count as a good showing. With his victory having been considered a given since the first ballot of MPs last month, the precise size of his majority will determine the sort of snap judgement Westminster collectively reaches on his campaign — and his mandate to lead. If Johnson does a Swinson and then some, with the properly lopsided victory his team anticipate, then expect him to be written up as the unquestioned and unquestionable ruler of all he surveys. Conversely, expect to hear a lot of questions about the frontrunner's much vaunted campaigning genius and popularity should he muster anything less than 60 per cent of the vote. And for the next prime minister, a bigger margin should make it easier to secure the compliance of a divided parliamentary party. Yet for some Tories, that question is irrelevant. As much as its exact scale will preoccupy Westminster today, those who are opposed to Johnson and his Brexit policy worry that the mere fact of his victory is the only thing that really matters when it comes to the Conservative Party's electoral prospects. David Gauke is among them, and the outgoing Justice Secretary uses an interview in today's Times to warn his party not to underestimate Swinson, arguing that a no-deal platform would leave the Tories "significantly out of touch" with its voters in London and the home counties. In her acceptance speech yesterday, Swinson made a convincing pitch for precisely those voters — repeatedly lumping Johnson with Nigel Farage. Lib Dem strategists believe their path to serious numbers in the Commons runs through Tory-held seats in the shires and suburbs, many of which turned yellow in May's local and European elections. But are Conservative MPs listening? One of the forgotten arguments of this leadership election was over just who was best placed to stem the tide voters to Swinson's party, which Matt Hancock – remember him? – diagnosed as just as profound a challenge for the Tories as the return of Farage. Despite the Damascene conversions undergone by Hancock and others since then, the problem hasn't gone away – in fact, Swinson's election is likely to exacerbate it. As much as Johnson, his supporters, reluctant conscripts and job-hunters stress the electoral cost of failing to deliver Brexit by 31 October, the price they pay at the polls for doing so via a no-deal could be just as steep. › Five things you need to know today: Johnson set to be elected as Tory majority evaporates Patrick Maguire was political correspondent at the New Statesman. Subscribe For more great writing from our award-winning journalists subscribe for just £1 per month!