Nigel Farage’s Brexit Party gave Boris Johnson’s Conservative Party a big win on Monday. It should assist the Conservatives in their quest to win a majority in the upcoming Dec. 12 election.

The Brexit Party did so by agreeing not to run candidates in Conservative Party-held seats. As the only major party actively promising to fulfill the 2016 Brexit referendum vote, the Conservatives are well-placed to use Farage’s decision to consolidate the pro-leave vote in their favor. Considering the frustration of many Labour-inclined voters to their party’s hesitant Brexit policy under current leader Jeremy Corbyn, the Conservatives should expect to increase their majorities in constituencies that voted to leave the European Union in 2016.