S&P 500 and the AI Trade Rebound on Election Day 2026

On US midterm election day, the S&P 500 closed about 0.4% higher at 7,568, according to Kiplinger. Investing.com reported a 0.36% gain, and the Nasdaq also finished higher. It snapped a three-day losing streak for the index.

Popular index funds tracked the move, which is why searches for SPY and VOO trended alongside the index itself.

The rebound only makes sense against the week before it. On Friday, October 30, the Nasdaq fell 2.9% and the semiconductor index dropped more than 7%, InvestorPlace reported. Alphabet lost close to $500 billion of market value after its earnings.

The worry was money. Big tech companies are spending record sums on AI data centers, and more of it is now borrowed. Meta, Microsoft and Oracle have all raised new equity or debt to fund AI. At the same time, the Fed held rates at its October 28 meeting with two officials voting for a hike, and Chair Kevin Warsh was reported to have said that higher rates do reach AI investment.

Read more in Kevin Warsh’s AI stock market comments, explained.

The headline gain hid a split market. Bloomberg reported that most S&P 500 companies fell on November 3 even as the index rose. Goldman Sachs’ trading desk described the move as driven mainly by large caps.

That happens because the S&P 500 is weighted by market value. When Nvidia, Microsoft, Broadcom and a few other giants rise together, they can lift the index while hundreds of smaller companies slip. Apple fell on the day after mixed earnings, which shows the AI trade, not big tech as a whole, did the lifting.

For index investors, narrow rallies are a reminder of how concentrated the S&P 500 has become in AI-linked names. It is not a reason to buy or sell on its own.

Two AI hardware companies reported after the bell and kept the theme going:

• AMD posted record revenue of $13.4 billion, with data center sales up 97% to $8.5 billion, and guided the fourth quarter to about $17 billion. See AMD Q3 2026 earnings.
• Super Micro reported about $19.9 billion of revenue against about $16.3 billion expected, and guided higher, though its gross margin fell to 12.8%. See SMCI stock after earnings.

Both shares rose in after-hours trading, then gave back some gains as election results arrived. Results like these feed directly into the debate about whether AI spending is a bubble or a buildout: they show the spending is real, and that it is turning into revenue for the suppliers.

Behind every move in the AI trade is physical construction: power lines, substations, cooling plants and buildings full of racks. CoreWeave, Nebius and Applied Digital, three of the day’s biggest gainers, all build or run AI data centers.

Stock prices swing on sentiment, but the facilities have to be planned on fundamentals: electricity cost, cooling, construction cost and payback. Those vary hugely by location. Power in Quebec, Manitoba or Washington costs a fraction of what it does in parts of California or the Northeast.

Our AI Build Configurator turns those fundamentals into numbers for every Canadian province and US state. It is free to try and available to license for your own site.