The gospel music from Mount Hebron Missionary Baptist Church spills into the streets of Sunnyside, a predominantly Black neighbourhood in southern Houston.

It is a familiar scene on any given Sunday: hands in the air, immaculate bow ties on starched shirts, fabric flowers adorning perfectly pastel hats. But with the US midterm elections just two days away, the service held a special significance on the front line of a US redistricting battle Mt Hebron had long been located in the ninth congressional district, its politically engaged Black voters for two decades helping to elect Democrat Al Green, a flamboyant presence in Congress known for his cane-waving opposition to US President Donald Trump. But following an appeal from Trump, the Republican state legislature last year conducted rare mid-decade redistricting, redrawing the church and its Black community into the Black-majority 18th district.

Critics call the process “cracking and packing”, diminishing the representation in Congress of minority groups, particularly heavily Democratic Black communities, by consolidating their voting power into fewer districts.

“It’s kind of one and the same when we talk about the voting and the civil rights,” said Pastor Max Miller, who has served at the church for 18 years.

“They are trying to manipulate and monopolise the vote and minimise the people who are in those districts,” said Miller.

“We see so much rolling backwards that it looks like they’re trying to take a script from an old song and turn back the hands of time.”Mount Hebron Missionary Baptist Church in Houston, Texas [Joseph Stepansky/Al Jazeera] As a result of the redistricting, Green was forced to run in a primary against 18th district incumbent Christian Menefee, another Black Democrat. He lost, and Houston lost one of its Black representatives in Congress. The ninth district, meanwhile, was redrawn to favour Republicans, one of at least five US congressional seats the party hopes to pick up in the midterm vote.

The machinations have resonated with worshippers at Mt Hebron. “I don’t like the redistricting at all because Al Green was moved out,” said 97-year-old Alice Jefferson, who had followed the congressman throughout his political career.

“He always had good advice for the people.”Voter Alice Jefferson, 97, is seen in the Sunnyside neighbourhood of Houston, Texas [Joseph Stepansky/Al Jazeera] Janice Ray, a 61-year-old home health aide and entrepreneur, said state lawmakers were “trying to move people out of the district that they’re familiar with”. “To me, it was all a bunch of BS,” she said.

“There was no reason for it.”“But we’ll stand firm, regardless of what they try to do,” Ray added.

“Because just like it was changed, it can always be changed back.”‘Voices have been weakened’The redistricting process has undergone a generational transformation this election season, one that, experts say, has degraded longstanding guardrails protecting minority voting power.

“In political science, we have what we call descriptive representation,” Michael Adams, a professor at Texas Southern University in Houston, told Al Jazeera. “In terms of descriptive representation, minorities and others feel that if they can elect someone who reflects their values, for example, and who may look like them, their voting can be defined as one voice.”“And certainly with not having an additional Black member of Congress representing Houston, a significant segment of Black voters may feel that their voices have been weakened,” he said. Texas was only the beginning.

This year Republican and Democratic state legislatures across the country joined the spree: Republicans successfully redistricted in Missouri, North Carolina, Tennessee, Louisiana, Alabama, Florida and Ohio; Democrats did so in California, while a court-ordered map in Utah handed Democrats a favourable seat. A Democratic push in Virginia was subsequently invalidated.

Redrawing maps mid-decade, and not waiting for the latest demographic numbers from the US census, was already atypical. But many of the maps drawn this year would have been deemed illegal in previous cycles.

Section 2 of the landmark Voting Rights Act of 1965, initially passed to counter blatantly racist voting practices in the US, had long prohibited redrawing congressional maps to dilute the electoral power of minority voters.

In April, the conservative-dominated US Supreme Court ruled that anyone challenging such a map must prove “racist intent”. Critics have said the ruling effectively allows for racial gerrymandering, with proving such an intent an unreasonably high bar.

But critics of Section 2 of the Voting Rights Act have said drawing maps to protect minority voting power is in itself discriminatory.

Defenders in Texas, meanwhile, have said the redistricting was based on the shifting political makeup of the state, and not racial gerrymandering.

“This plan includes political considerations, public testimony, recognition of population growth and recent changes in voter trends,” State Representative Todd Hunter, a Republican, said shortly after the new map’s passage last year.

“Each of these newly drawn districts now trend Republican in political performance. While there’s no guarantee of electoral success, Republicans will now have an opportunity to potentially win these districts,” he said.

A political test There are no guarantees that a party’s redistricting plans will actually work.

Following the tit-for-tat map redrawings, Republicans hoped to net at least 13 seats nationally. Polling has suggested their gains may be much more muted.

All told, about 35 million US voters will be casting ballots in newly redistricted seats this election.

“Redistricting can change the political boundaries, but it can’t guarantee how voters will behave,” Brandon Rottinghaus, a professor at the University of Houston, told Al Jazeera.

In Texas, the Republican map was drawn largely based on recent Latino voting trends. The demographic swung heavily for Trump in the state in 2024, despite once being considered a reliable Democratic voting bloc.

Beyond the ninth congressional district in Houston, Republicans hoped to pick up four other districts, most based in South Texas, with an eye on shifting Latino sentiment.

But the political tides have again turned. Trump’s popularity has tanked among Latino voters, fuelled in part by unrest over the economy and the administration’s aggressive deportation campaign.

It remains to be seen how that will reflect at the ballot box when Texas voters pick a senator, governor, members of Congress and a slate of state and local officials.

“These districts are a test of whether political dissatisfaction can overcome an aggressively partisan map,” Rottinghaus said. ‘Trying to mobilise’

With new boundaries come new opportunities. The ninth district is now considered Republican-favoured, but its large population of low-propensity Latino voters creates a pathway for a Democratic victory, according to Dayana Iza, Texas state director of Mi Familia Vota, a Latino voting organisation that has focused resources on the congressional race.

The state legislature “kept a big portion of Latino voters there, but the reality is that the Latino percentage in that district that votes is very, very low,” Iza told Al Jazeera. “So that then became a district that we are trying to mobilise in terms of turnout.”On the Saturday ahead of the November 3 vote, Democratic candidate Leticia Gutierrez and State Senator Molly Cook zigzagged through a neighbourhood of single-family homes in eastern Houston.

US congressional candidate Leticia Gutierrez, left, and Texas State Senator Molly Cook knock on doors in Houston, Texas [Joseph Stepansky/Al Jazeera] Any path to victory, Gutierrez assessed, would be based on face time and a chance to connect with disillusioned voters.

“This community here has an average annual income of $63,000 a year. I make a little over that, and it’s difficult,” Gutierrez told Al Jazeera. “At this point, it’s not a left or a right thing anymore. This is an affordability crisis.”

“You’ve heard some of the voters out here say this is the first time someone actually came to my door,” she added. “That means a lot, and so we want to continue to do that.”Among the residents was Christian Garcia, a 53-year-old who works at a local chemical plant and has not voted since moving to Texas from Puerto Rico in 2014. He said he is focused on his family, saving enough for retirement and eventually leaving some money behind for his adult children.

Voter Christian Garcia stands in his garage in Houston, Texas [Joseph Stepansky/Al Jazeera] In the past, Garcia said, he felt voting was “wasting my time”.

“You know, it’s a lot of corruption and things,” said Garcia. “I just don’t believe in anybody anymore.”Down the block, Esmeralda Gil, a 39-year-old teacher, said she hoped for a Democratic surge.

Gil questioned why taxes, particularly on housing, seemed so high, while so many struggled to access healthcare. “We need affordable healthcare and affordable housing,” she said.