How data centres became the sleeper issue that could decide the US midterms Democrats and Republicans alike are coming out against data centre development, amid growing backlash across the US. By Kali Hays A year ago, a longtime US senator was not thinking much about data centres.

Now, according to one of his advisers, he is having regular meetings with staff to track their impact and working on new legislation aimed at curbing their rapid expansion across the country.

"This happens sometimes, something starts slow and then it goes fast", the senior policy adviser to the Democratic senator told the BBC. The person spoke on condition of anonymity as they are not permitted to speak to the press.

The 180-degree turn in this senator's attention was driven almost entirely by a growing wave of public backlash that has seen politicians across the country scramble to keep up. Public sentiment has turned against the expansion of data centres, the large warehouses that store processing power needed for internet activity.

Packed with rows and rows of computer chips, sometimes seven-feet high, data centres have turned into more than infrastructure for the internet. They are now the physical embodiment of the recent and explosive growth of artificial intelligence (AI) technology, and the varied fears people associate with it.

"I don't want to be the guinea pig for this," Indiana resident Angelita Soriano told the BBC. A backlash over data centres is another threat to the AI juggernaut A new Amazon data centre is being built directly across the street from her home. When complete, the 26-building structure will take up more than a square mile in her neighbourhood and maintain 782 diesel-powered generators.

Some data centres are even larger. In Ohio, a joint effort between OpenAI, Nvidia, SB Energy and the US Department of Energy is set to build a data centre complex that will stretch for roughly six square miles, the same size as most townships in the US.

There are about 3,000 data centres currently operating in the US, with that number potentially doubling in the next few years, according to a report by Pew Research Center.

Data centres are built through very local rules and permits, meaning federal lawmakers like US senators have little say in the process.

Yet, opposition has become so strong so quickly in the US that suddenly, politicians at all levels are now all but required to take a stand.

"This isn't just an issue on the left, there is huge pushback among conservatives to data centres," Chloe Autio, an AI policy adviser, said. "Whoever articulates a clear position and sticks to it, in either party, really stands to benefit." Her analysis was echoed by the adviser to the US Senator working on data centre legislation.

"There is a clear policy need here that we're looking to fill," he said. "This is a major backlash across the country - constituents are seeing the impacts of data centres and they do not like them." That has put many on Capitol Hill - even Republicans - in direct conflict with President Donald Trump, who has championed the unrestrained growth of AI technology.

Trump has dubbed the backlash to data centres a "sick conspiracy" and said people and towns working to keep the buildings out are "backwards and poor".

His ire has been used as a boon to Democratic politicians looking to draw midterm votes from unhappy or undecided constituents.

The BBC spoke to residents of Indiana, Arizona, Michigan, Pennsylvania and Oregon, all of whom have been organising locally against the development of data centres. They expressed concerns about many aspects of the buildings, including their size, construction and operational noise, their impact on air, water and energy resources, as well as the speed at which they seem to be approved by local authorities.

During the first few months of this year, community groups organising against data centres more than doubled to 833, cropping up in almost every US state, according to research from Data Center Watch. The firm collects data for AI industry stakeholders and is part of an AI startup 10a Labs.

Stephanie Maldonado, the political director of LUCHA, a community organising group based in Arizona, referred to the push back against data centres as "a David and Goliath story" that began several years ago.

"People have been ready to put a stop to it," Maldonado added. "Now, people are angry." New national polling shows that AI regulation and data centres are among some of the top issues for voters this election cycle, behind the ongoing Iran War and various aspects of the economy.

Proponents of building data centres often argue the projects will create more, and better paying, local jobs.

Yet, recent research from Brookings Institution, a non-partisan policy research group, found that a new data centre creates between 100 and 200 local jobs, which is "fewer than industry advocates claim". The projects also have essentially no impact on local wages.

Arizona Governor Katie Hobbs was one such proponent - until public pressure pushed her to the other side of the issue. In July, she enacted a three-year pause on any new tax break given to a company for a data centres project.

Arizona is far from the only state to see politicians react to data centre backlash.

Abdul El Sayed, a Democrat running for Senate in Michigan, made new rules and regulations for data centres a clear part of his successful primary campaign for Senate.

In the race for governor of Georgia, a Democrat who is calling for a pause on data centre development is in a dead heat with a Republican who disagrees.

Republican Senator John Husted of Ohio, who is fighting to keep his seat against Democrat Sherrod Brown, has also had to shift his position. Recent polls have found that the majority of Ohio voters oppose data centres. He has softened his support, saying that their arrival should be up to local citizens and elected officials.

Meanwhile, Brown has stumped on his opposition to new data centres. He leads Husted in recent polls.

Husted's trouble in Ohio led the National Republican Senatorial Committee, the major fundraising arm for conservatives in the Senate, to write in a private memo that Republican politicians needed to entirely reframe how they spoke to voters on data centres. "This has become a sleeper issue for the entire election cycle", the NRSC added.

Texas is perhaps the most clear cut example of how backlash has turned into an undeniable issue for even the most pro-business politician.

The state currently has almost 300 operational data centres, with another 170 planned for development, according to Pew data.

At the end of last year, Republican Governor Greg Abbott had boasted of Texas as "the epicentre of AI development" because of the number of data centres it housed.

Within months he was backtracking, citing concerns of "safety and quality of life". It could play a part in the state's upcoming senate race too.

Democrat James Talarico's campaign is pushing for an end to "sweetheart tax deals" for Big Tech. He's now seen as a frontrunner for the historically Republican seat, where he is facing off against Republican Attorney General Ken Paxton.

Paxton said in a late September interview that there was still "plenty of open space in Texas that we can put data centres".

Many of the actions or proposals that have come from politicians looking to appease or address these voters are temporary. Most of the moratoriums, for instance, will end in one to three years.

It is possible that the political winds will have shifted by the time such moratoriums expire, leaving Big Tech and AI firms to build as they wish. For now, people's feelings toward them are strong.

Balaji Tammabattula, the chief executive of Barupon, is developing a roughly 700-acre data centre and technology campus in Liberty, Texas. Despite the buildings being designed to use rain capture for water and supply its own energy needs, an increasingly common design for major data centre projects, Tammabattula told the BBC that people in the community oppose the project out of hand.

"There's just such a high level of tension from the jump that you can't really even break through with the facts," he said.

During a recent community event, Tammabattula said he tried to speak one-on-one with a woman who was vociferously opposed to the project.

"She just looked right at me and said, 'Get the hell out of my state.'" GUIDE: What are the US midterms?

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