Theresa May's surprise announcement that a general election will be held June 8 sent Britain's political journalists scrambling back to London from their Easter vacations. A vicar's daughter with a reputation for cautious pragmatism, May was chosen as a safe pair of hands to replace David Cameron as prime minister after the latter's Brexit referendum gamble ended in defeat. In calling a general election, May has shown she is willing to take a gamble of her own.

Why would the reputably risk-averse May call an election now, three years before the next scheduled national ballot in 2020? There are three main reasons. First, she is likely to win. Opinion polls suggest that holding an election now is no risk at all. A YouGov survey of voting intentions on April 12 and 13 shows May's governing Conservative Party more than 20 points ahead of the main opposition Labour Party. Given their lead in the polls, Conservative members of Parliament have been pushing a reluctant May to call an election since she took office last summer. May's initial hesitancy was not unfounded. U.K. opinion polls have a history of inaccurate performance, most recently failing to predict Cameron's election victory in 2015. But when the polls have been wrong, they have usually underestimated Conservative support relative to Labour. That is good news for May.

Her confidence is further bolstered by Labour's civil war. Left-wing leader Jeremy Corbyn does not command support among the majority of more moderate-inclined Labour MPs. Nor is Corbyn's standing any better outside Parliament. Asked who would make the best prime minister, only 14 percent of British voters chose Corbyn, compared with 50 percent citing May. Corbyn is already a bogeyman in the Tory press. With the election campaign underway, May's media allies will further decry Corbyn as a dangerously radical and incompetent leader — ignoring the paradox of their propaganda. May hopes that Labour's strife will translate into an increased majority for the Conservatives. But it is not only Labour's woes she seeks to exploit with an early election.