Harris County, Texas, already a contentious hot spot for legal challenges on voting, closed down 90% of its drive-thru balloting sights, pointing to laws requiring a structure to serve as a polling location.

A federal judge on Monday overruled a challenge from state Republicans to throw out some 127,000 ballots already cast at drive-thru polling stations in early voting. The challenge was dismissed because Republicans had no basis to file an objection to those votes, the ruling found.

But later, Harris County Clerk Chris Collins said votes could be at risk from voting in tents used as drive-thru polling centers, shutting down nine of the 10 drive-thru centers in the states most populated county. A spokesperson for the county clerk’s office told CNN that “walls and a roof” are required to support a court ruling that voting takes place in a “structure.”

Harris County is considered a Democratic stronghold in a state that usually goes to the Republicans in the general election. Republicans spent much of October in court seeking clarification on voting tactics.

During the weekend, state Sen. Carol Alvarado, a Democrat representing the Houston area, urged people to use free legal help in federal challenges to state election laws in order to “protect your vote.” Democrats in the state cautioned against federal intervention in state election laws in general.

The contentious political landscape was put on display last week when supporters of incumbent President Donald Trump, a Republican, took to a Texas highway and surrounded a bus full of campaign workers for former Vice President Joe Biden and his running mate, Sen. Kamala Harris, D-Calif.

Neither candidate was on the bus at the time, though the FBI is investigating the incident. The Biden campaign accused Trump supporters of trying to run the bus off the road. Authorities intervened to escort the bus to its Austin destination.

People wait in line to cast their ballots at an early voting location in Smyrna, Georgia
People wait in line to cast their ballots at an early voting location in Smyrna, Georgia AFP / Elijah Nouvelage