Dozens of Democrats in the Texas legislature faced possible arrest Monday after fleeing the US state to block a redrawing of districts in Republicans' favor ahead of the 2026 midterm elections.

The state's Republican leaders, following a push by President Donald Trump, plan to shift congressional district borders such that five seats become likely to flip from Democratic control.

The contentious but legally permitted move, known as gerrymandering, seeks to help Republicans retain control of the US House of Representatives in next year's midterms, when the opposition party usually does more favorably.

State lawmakers draw legislative maps themselves in Texas, like in many other states across the country, but usually only do so once every 10 years following the national census.

Democrats are in the minority in the Texas legislature, but enough members have fled the state to deprive the body of a quorum necessary to do business.

"This is not a decision we make lightly, but it is one we make with absolute moral clarity," Gene Wu, chair of the Texas House Democratic Caucus, said in a statement.

The lawmakers left the state Sunday and most headed to Democratic-controlled Illinois, whose Governor JB Pritzker told a news conference that he would "protect" them.

They face at minimum a $500 fine per day of absence. But Texas Republicans raised the stakes, passing a motion to issue warrants for the missing Democrats' arrests.

The warrants apply only within the state, however, meaning the missing legislators could only be detained on their return.

Governor Greg Abbott, a close Trump ally, has also threatened to push for the lawmakers to be expelled, saying their absences amount to "an abandonment or forfeiture of an elected state office."

Democratic lawmakers have dismissed Abbott's threats as bluster, with state representative Ann Johnson on Monday telling CNN, "I think it shows how desperate they are."

Abbott, who ordered the special session on redistricting, has sought to pile on the political pressure by concurrently calling for votes on disaster relief related to the state's catastrophic flooding last month, which killed over 130 people.

Wu said the move by Abbott "has turned the victims of a historic tragedy into political hostages."

"We're not walking out on our responsibilities; we're walking out on a rigged system," he added.

- Domino effect -

Gerrymandering has been at the center of long-running political dispute in the United States, especially as computer-assisted analysis helps refine map-making.

Some Democratic-led states have also drawn maps steeply favoring their party -- including Illinois -- but the conservative-dominated US Supreme Court has ruled for now that only state courts can decide on the legality of partisan redistricting.

The Texas push to redraw its maps mid-decade has set off a scramble of other states to potentially follow suit.

Democratic-led New York and California are considering moves to pencil out Republican seats -- but, unlike Texas, they have previously enacted legal constraints against such practices, deeming them undemocratic.

Leaders in those state have signalled they would seek to push through those measures to respond to Texas.

"This is a war. We are at war," New York Governor Kathy Hochul told a press conference, as she welcomed some Texas legislators to her state.

"That's why the gloves are off. And I say, bring it on."

All 435 US House seats are up for election in 2026, with Republicans currently narrowly controlling the chamber by single digits.