Eric Cantor

WASHINGTON — Repudiated at the polls, House Majority Leader Eric Cantor announced Wednesday that he will resign his leadership post at the end of next month, clearing the way for a potentially disruptive Republican shake-up just before midterm elections with control of Congress at stake.

Cantor informed fellow Republicans of his intentions at an emotional closed-door meeting, then made his public announcement at a news conference where he appeared upbeat, all less than 24 hours after losing Virginia’s GOP primary election to David Brat, a little-known and underfunded rival backed by tea party groups.

Lawmakers in both parties said Cantor’s defeat and the prospect of a change within the Republican high command probably signal the demise of immigration legislation along the lines President Barack Obama is seeking and will also have a negative impact on the balance of his second-term agenda.

Republicans set leadership elections for June 19. Even before Cantor’s announcement, jockeying had broken out among fellow Republicans eager to move up the House leadership ladder — or establish a foothold on it.

Rep. Peter King, R-N.Y., said he was worried that Cantor’s loss may lead to even more gridlock.