Republicans spent more, Democrats won more: Inside the costliest US midterm battle

Republicans lose US midterm despite record spending

The 2026 US midterm elections saw record campaign spending, with Republicans spending a whopping 60% more than Democrats but still lost seven stronghold seats. The results also reflected growing opposition to data centre projects and a shift in Latino voters' support towards Democrats. The party won both chambers of Congress despite Republicans spending significantly more on Senate races. The elections also showed a change in voting patterns across several states, with many Latino voters moving back towards Democrats after backing Republicans in recent elections. The 2026 midterm elections are expected to be the most expensive in US history, according to nonpartisan watchdog group OpenSecrets. Outside groups and independent committees spent at least $2 billion on the US Senate races, Reuters reported. This was separate from the money spent directly by candidates. Texas was among the biggest spending battlegrounds. Elon Musk, the world's richest person, and other wealthy Republicans spent $316 million to support state Attorney General Ken Paxton, who struggled to raise money for his campaign. Democratic groups spent $109 million backing James Talarico, whose campaign raised more than $146 million directly. Ohio and Michigan also saw spending run into hundreds of millions of dollars, with the amount swelling more as the Election Day approached. Political groups also changed where they spent their money as the chances of candidates shifted. Spending in Georgia and North Carolina fell as Republican candidates lost ground. At the same time, more money went into South Carolina, Mississippi and Kansas as competitive races emerged in states that were earlier considered safe for Republicans. Outside groups were able to move their spending quickly between states as the election picture changed.

Voters push back against data centre projects

Opposition to data centre projects also gained support during the elections. Voters across 10 states backed restrictions on data centre development or rejected plans to build such facilities in their neighbourhoods. According to tracking by Redbud Consulting, 40 of the 41 ballot measures restricted the setting up of data centres. In most counties where these measures were put to a vote, voters also shifted strongly towards Democrats. The election results were followed by a fall in shares of companies linked to artificial intelligence and data centres. These stocks declined in the days after the polls amid expectations of tighter oversight under a Democrat-led US Congress.

Record number of Latino voters shift towards Democrats

A major change in the elections came from Latino voters, many of whom moved back towards Democrats after helping Republicans gain ground in recent elections. The shift was seen across different parts of the country, from Texas border counties and meatpacking towns in southwest Kansas to Miami-Dade, Colorado and Arizona. A record number of Latinos voted in the elections, with the figure reaching as many as 14.5 million, said Janet Murguía, CEO of UnidosUS, the largest US Latino civil rights organisation. “Latino voters sent a clear message about their anger and concern about the direction of our country,” she said. The change in Latino voting patterns was part of a larger shift among voters from different racial backgrounds. This broader coalition helped Democrats return to power and win both chambers of Congress, with victories across the country.

Republicans lose support in majority-Latino counties

The shift towards Democrats was also clear in voting data from counties with large Latino populations. Across 64 majority-Latino counties with Senate races where most votes had been counted, Republicans lost 14 percentage points from their 2024 vote share, according to Reuters. This drop was larger than the national trend. In Hidalgo County, Texas, Republican support fell by around 25 percentage points. In Miami-Dade, Florida, a county Trump won in 2024, it dropped by 10 percentage points. These figures show the scale of the shift in Latino voting patterns across key parts of the country.