For a day, the market seemed to welcome the midterm result. On Wednesday, as it became clear that Democrats had won control of both chambers of Congress, the Dow Jones Industrial Average jumped more than 1,500 points. NPR's economics correspondent put part of that rally down to simple relief: the outcome was decisive, and there would be no weeks of legal limbo. Some economists added an old line from the trading floor, that markets like divided government because it limits what Washington can do.
On Thursday the mood turned sharply. According to CNBC, the S&P 500 fell about 4.4 per cent, the Dow lost roughly 1,833 points, or 3.4 per cent, and the Nasdaq Composite dropped 5.5 per cent. That left the Nasdaq more than 10 per cent below its recent high, which is the usual definition of a correction. For all three indexes it was the worst single day since 4 April 2025, when President Donald Trump's "Liberation Day" tariffs shook markets around the world.
This was not a general loss of faith in the US economy. It was a targeted sell-off in the companies behind the artificial-intelligence build-out. CNBC reported that Micron Technology and Advanced Micro Devices each fell about 17 per cent, the cloud provider CoreWeave lost about 10 per cent, and Nvidia fell more than 9 per cent, wiping out its gains for 2026. The "Magnificent Seven" technology giants lost more than $1 trillion in market value between them, with Nvidia alone accounting for more than $440 billion. The information-technology sector of the S&P 500 fell 7.3 per cent, its worst day since the first weeks of the pandemic in March 2020.
The explanation offered by traders, analysts and the financial press was the same: the election had put the physical side of the AI boom on notice.
The clearest signal came from local ballots, not from Congress. Ballotpedia, the non-partisan elections encyclopedia, tracked at least 50 local ballot measures on data centers in 13 states in 2026. Most were decided on 3 November. By 4 November, voters had decided 47 of them, and in 46 the majority favored tighter limits on data-center development. The one exception was Harwood, North Dakota, where voters rejected an extra review requirement for some industrial projects.
CNBC, counting the election-night measures alone, found 41 in ten states. Ohio accounted for 21. The Guardian reported that at least 14 Ohio municipalities passed bans or restrictions, including Sunbury, where Amazon had proposed a $2 billion project. It also reported that eight towns in Maine approved temporary moratoriums, and that voters in Emporia, Kansas, approved a ban on "high-impact" data centers after a gigawatt-scale campus was proposed there.
The issue also shaped the top of the ticket. CNBC reported that Democrat Sherrod Brown beat Republican Senator Jon Husted in Ohio after calling him "the face of data centers," and that Ohio's next governor, Democrat Amy Acton, backs a "conditional moratorium": data centers would have to cover all of their utility costs and be built with union labor. In Texas, Democrat Gina Hinojosa defeated Governor Greg Abbott after accusing him of putting the tech industry ahead of local communities. The Guardian reported that Georgia's governor-elect, Keisha Lance Bottoms, has also promised moratoriums on large data centers.
According to a CNBC voter poll, 56 per cent of voters said data centers were a crucial or major factor in their vote, and Democrats rated the issue higher than Republicans did. Semafor reported an analysis showing that Democrats in more than 130 federal and gubernatorial races ran anti-tech or anti-data-center advertising this cycle.
For investors, the most important result may have been in Austin. The analyst Dan Ives, quoted by the Guardian, called Texas the state "where 25%-30% of data center gigawatts and capacity will come from," and described the governor-elect as a "known anti-datacenter politician." CNBC reported that Hinojosa told CNN the state would still work with Elon Musk's companies, but "on our terms," and that she said Texas needed to "stop what we are doing with data centers until we have measures to protect Texans." CNBC also reported that she asked the state parks agency to pause talks about selling public land to SpaceX.
The ballot results added to doubts that were already there. CNBC noted that chipmakers and data-center companies had been selling off in October over rising interest rates and heavy spending. It also reported that the four biggest cloud spenders, Alphabet, Amazon, Microsoft and Meta, are each spending hundreds of billions of dollars a year on AI infrastructure, and that all except Microsoft have turned cash-flow negative as a result. When an industry needs land, power, water and permits on that scale, a wave of local refusals and new governors who support moratoriums is a serious financial risk. Semafor reported that banks and asset managers financing the build-out had already begun treating local opposition as a credit risk.
The sell-off spread overseas. CNBC reported that Japan's Nikkei 225 fell into a bear market on Friday and that South Korea's Kospi dropped so sharply in early trading that circuit breakers halted it for 20 minutes. Chip and equipment makers in Taiwan, Japan and South Korea fell heavily.
President Trump gave his own explanation on Thursday night. "The Stock Market crashed today because the Dumocrats had a big Tuesday — So sad to see, you only have yourselves to blame!" he wrote on Truth Social, as quoted by Axios. Axios noted that he had been quick to take credit for Wednesday's rally.
His argument has some basis. The scale of the Democratic win and the clear market reaction to the data-center results are connected. Musk, who CNBC says was the cycle's largest individual donor with at least $474 million spent, reacted to the results with a sarcastic post: "Data centers in space looking pretty appealing right now."
But the timing does not fit neatly with the idea of a market punishing the result. The vote was on Tuesday, stocks rallied strongly on Wednesday, and the sell-off came on Thursday. Axios called it "an unusually delayed reaction." Several other pressures were present that day. CNBC's live coverage cited the risk of renewed US military action against Iran, with one energy analyst putting the odds of a resumption of fighting at 80 per cent and Brent crude trading around $100 a barrel. It also noted futures pricing that showed about a 70 per cent chance of a quarter-point interest-rate rise at the Federal Reserve's 9 December meeting. A friendly rate environment has supported much of the AI rally, so the prospect of higher rates matters to these stocks.
Several economists also argue that slower data-center growth would not be bad for the wider economy. Joe Brusuelas, chief economist at RSM, told NPR that limits on data centers and AI could produce "a better-balanced economy, a better-balanced composition of growth," because other industries have had to compete with AI for power, land and workers. Other market voices saw Thursday's fall as overdone. Victoria Greene, chief investment officer at G Squared Private Wealth, told CNBC that "the AI trade, in my opinion, is not dead here," and called the fall "a good discount."
There is a gap between what has been decided and what has only been promised. The local measures that passed are real restrictions in those places, although some will face legal challenges. A governor-elect's promise of a moratorium is only a promise until it is enacted, and it will have to pass through state legislatures, utility regulators and courts.
The new Congress is different again. Democrats will not take control until January, and the President keeps his veto. At the federal level, Democrats' first move will probably be investigation rather than legislation. Representative Greg Casar of Texas, who chairs the Congressional Progressive Caucus, said "AI company CEOs should be called to testify under oath." Representative Robert Garcia of California, expected to chair the House Oversight Committee, put it in two words: "Lawyer up." Statements like these say what Democrats intend to do. They are not laws.
For investors, this means the federal policy picture could be clearer than the state and local one. Divided government in Washington makes major federal AI legislation, in either direction, harder to pass. The new pressure is coming from county commissions, town ballots and governors, and those are harder for national companies to lobby and slower to resolve.
The election has turned a technical industrial question into a political test for both parties.
Republicans have long presented the AI build-out as a matter of national strength and competition with China. They will need to decide whether to defend it more strongly or adjust to voters who, in places as conservative as rural Ohio and Kansas, voted against the facilities. Semafor reported that Abbott had moved towards promising tougher regulation before he lost. The Guardian noted that Florida's Republican governor, Ron DeSantis, signed strict rules on large data centers in May. The backlash against data centers is no longer only a left-wing cause.
Democrats face a different risk. The party won partly by tying data centers to higher power bills and the influence of wealthy donors. If the build-out slows sharply and the economy weakens, Democrats will share the blame for the result. Brusuelas's view that the economy would be better balanced is one possibility. The other is an industry that pulls back faster than the rest of the economy can absorb.
Friday's October jobs report will add more information. Economists polled by Dow Jones expected 59,000 new jobs and an unchanged unemployment rate of 4.2 per cent. Whatever those figures show, the main lesson of this week is already clear. The AI economy depends on physical sites, and the people who live near those sites have shown they will vote on them.