Democratic state lawmakers have fled Texas in an attempt to stop a vote on a new congressional map that would heavily favour Republicans.
The map, unveiled by Texas Republicans earlier in the week and backed by President Donald Trump, contains redrawn districts that would help preserve the party's slim majority in the US House of Representatives.
Two-thirds of the 150-member Texas House must be present in order to hold a vote. Fifty-one Democratic lawmakers have fled to Chicago, denying Republicans the required quorum.
They said they plan to stay away for two weeks until the end of a special legislative session convened by Texas Republican Governor Greg Abbott to hold the vote.
Each of the 51 lawmakers could face a $500 (£380) fine for each day they are away, and Texas Attorney General Ken Paxton, a Republican, had previously threatened to arrest legislators who break quorum.
