Sen. Bernie Sanders did not wait long to tell Democrats what he thinks their new majorities should do about artificial intelligence. At 6:59 p.m. ET on Wednesday, a day after Democrats won control of both chambers of Congress, the Vermont independent who caucuses with them posted on X: "NATIONAL DATA CENTER MORATORIUM NOW."
By the close on Thursday, the stocks most tied to the AI building boom had taken their worst beating in more than a year. The Nasdaq Composite fell 5.52% to 24,315.00. That left it 11.9% below its Oct. 6 record close and in correction territory, Wall Street's term for a drop of at least 10% from a peak. The S&P 500 lost 4.36% to 7,353.73, and the Dow Jones Industrial Average fell 1,833.06 points, or 3.44%, to 51,523.06. CNBC reported that it was the worst day for all three indexes since April 2025.
Sanders' post was not the only thing weighing on the market. But it put into words the fear that ran through Thursday's trading: that a Democratic Congress, encouraged by a wave of local votes against data centers, could slow the spending that has powered the AI trade. Tim Holland, chief investment officer at Orion, said investors were "stepping away until they get a better sense of the implications of the midterms around the AI capex cycle," according to CNBC.
Chipmakers took the hardest hit
Semiconductor stocks led the decline. Advanced Micro Devices fell 17.3% and Micron Technology dropped 17.5%. Arm Holdings lost 13.1%.
Several of the market's AI leaders closed at their lowest levels in months:
- Broadcom fell 10.4% to $291.53, its lowest close since August 2025.
- Nvidia fell 9.3% to $181.60, its lowest close since early April.
- CoreWeave, which rents out AI computing capacity, fell 9.8% to $43.66. That was its lowest close since April 2025, its first full month as a public company.
- Oracle fell 6.9% to $115.16, within a few cents of its lowest close of the past year.
The damage spread well beyond chips. Tesla fell 10.8%, and CNBC estimated that the seven largest U.S. technology companies had lost close to $900 billion in combined market value heading into the final hour of trading. All 11 sectors of the S&P 500 were lower by midafternoon. Qualcomm added its own weight, falling 9.5% after it gave a weaker-than-expected outlook despite beating earnings estimates.
The Cboe Volatility Index, often called Wall Street's fear gauge, closed at 28.18, up from 16.61 a day earlier.
The turn was sharp. On Wednesday, stocks had rallied on reports that President Donald Trump accepted the election results and would work with Democrats. The Dow jumped 1,569.40 points that day, or 3.03%, its best session since April 2025.
What Sanders posted
The full post from @SenSanders, an account with about 11.5 million followers, read:
7 months ago, AOC and I introduced an AI data center moratorium.
— Sen. Bernie Sanders (@SenSanders) November 4, 2026
Last night, 43 of 44 communities voted for one locally.
Americans don’t want Big Tech oligarchs wrecking the environment, gutting jobs and threatening humanity’s future.
NATIONAL DATA CENTER MORATORIUM NOW
The post had been viewed more than 1.1 million times by Thursday evening, according to X's public count.
"AOC" is Rep. Alexandria Ocasio-Cortez, D-N.Y. In March, she and Sanders unveiled legislation that would halt construction of new AI data centers until national safeguards are in place. The Associated Press reported at the time that the bill was unlikely to advance in either chamber, and most lawmakers in both parties have rejected the idea of a nationwide pause.
Sanders' tally of local votes is close to, but not quite the same as, independent counts. Ballotpedia, which tracks ballot measures, listed 41 data center-related measures on local ballots in 10 states on Tuesday, 21 of them in Ohio. CNBC, working from Ballotpedia's list and its own results, found that voters sided against data centers in every one except Harwood, North Dakota, where voters rejected an added review of industrial projects. In Wells, Maine, more than 80% of voters approved a retroactive 180-day moratorium on data center development, Scientific American reported. Local results remain unofficial until they are certified.
Other Democrats joined in
Sanders was not alone. On Wednesday afternoon, Rep. Yassamin Ansari, D-Ariz., wrote on X that the "top of the Democratic agenda on day 1 needs to be a pause on advanced AI development, regulation of this out of control industry, and a ban on artificial superintelligence." Rep. Greg Casar, D-Texas, chair of the Congressional Progressive Caucus, amplified her post on Thursday, adding: "Yes!"
Some of Tuesday's winners had campaigned on the issue. Sherrod Brown, who is returning to the Senate after defeating Republican Sen. Jon Husted in Ohio, told supporters, "I do not work for data centers." In Texas, Democrat Gina Hinojosa, who unseated Gov. Greg Abbott, said in a campaign video in late October: "When I am governor, I will issue a moratorium, a ban, on all data center approvals until laws can be passed by the legislature to protect Texans." Texas is home to 27% of planned data center capacity, according to Wells Fargo figures cited by CNBC.
Voters said the issue mattered to them. In the CNBC Voter Poll, 56% of voters said AI and data centers were a crucial or major factor in their decision, and 65% of that group said they voted for a Democrat for Congress.
Elon Musk offered his own take on X: "Data centers in space looking pretty appealing right now."
A national moratorium is still far from law
A nationwide pause would need far more support in Congress than it has today. In July, House Democratic leader Hakeem Jeffries of New York, who is in line to become speaker when the new Congress convenes in January, told Politico that a moratorium was "certainly not a position that I've articulated at this moment."
Jeffries was responding to Rep. Frank Pallone, D-N.J., the top Democrat on the House Energy and Commerce Committee, who had said that "until we have some strong protections to address the cost to ratepayers and the environment, we should have a moratorium." Pallone, who is in line to chair that committee, would not say at the time whether he would pursue one.
Many Democrats have favored narrower rules. A bipartisan bill from Rep. Kathy Castor, D-Fla., and Rep. Gabe Evans, R-Colo., the Ratepayer Protection Act, would have states consider requiring large electricity users, such as data centers, to pay the full cost of new power generation and transmission upgrades.
Parts of the industry are already moving that way. OpenAI published commitments on Thursday that include paying the full cost of powering its data centers, CNBC reported. The Data Center Coalition, the industry's main trade group, has argued that the facilities bring jobs and tax revenue to the communities that host them.
Any national pause would also have to get past Trump, whose administration has pushed to speed up the construction of AI infrastructure. Overriding a presidential veto takes a two-thirds vote in both chambers.
What Sanders and other lawmakers own
Sanders has no stock trades on file. His most recent annual financial disclosure, filed Aug. 13 and covering 2025, lists bank and credit union accounts, mutual funds and annuities in his wife's retirement plans, and a pension from the city of Burlington, where he served as mayor in the 1980s. The report values his assets at $662,029 to $1.83 million. Senate forms do not require senators to list a personal residence that earns no income. Congress Stock Tracker puts his estimated net worth at about $1.2 million, using the midpoints of those ranges.
Ocasio-Cortez has no stock trades on file either.
Members who do trade had been active in AI-related stocks in the weeks before the election. Rep. Ro Khanna, D-Calif., whose disclosures list more trades this year than any other member's, reported both purchases and sales of chip stocks in August and September. The largest was a sale of Broadcom worth $50,001 to $100,000 on Sept. 23, from an account listed under a dependent child.
Rep. Gilbert Ray Cisneros Jr., D-Calif., reported sales of Nvidia, AMD, Broadcom and MACOM Technology Solutions between Aug. 18 and Sept. 29. Sen. Sheldon Whitehouse, D-R.I., and the spouse of Sen. Cory Booker, D-N.J., sold Nvidia shares in mid-August. On the buying side, Rep. David Taylor, R-Ohio, bought Broadcom on Aug. 26, and the spouse of Rep. Rick Allen, R-Ga., bought Broadcom on Aug. 12.
Those filings arrive with a lag. The STOCK Act gives members up to 45 days to report a trade, so any buying or selling around election week may not become public until December.