The most expensive Senate battles these midterms

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The US midterm elections have been equal parts expensive and bitterly fought. “Competitive races drive up the price tag of elections,” Brandon Rottinghaus, a professor in the University of Houston’s department of political science, told Newsweek.

For months, America has been inundated with political advertising funded by the world’s wealthiest person (Elon Musk), ordinary folk, and cashed-up PACs (political action committees, run by party headquarters or external groups, some of which do not disclose their donors).

Combined, these groups are expected to have spent a record $US11.6 billion ($16.5 billion) to influence these elections, which will determine whether the Democrats can neuter the final two years of Donald Trump’s presidency.

The Senate, where Democrats need to win four more seats for a majority, has attracted the biggest share of spending, about $US3.4 billion, according to AdImpact, which tracks ad spending. While down in the polls, the Republicans are not out – the party has about $US700 million more cash than the Democrats, allowing it to outspend its rivals by $US200 million in the most competitive Senate races, according to Bloomberg.

So, which Senate fights have attracted the most money, and why?

Texas

Traditionally red Texas is tipped to become the most expensive Senate race in the country’s history, as Democrat James Talarico takes on the state’s controversial Attorney-General Ken Paxton.

AdImpact said ads about the Texas stoush will add up to $US573 million, with Musk and PACs donating hundreds of millions to the Republican Paxton, while Talarico has raised $US134 million mostly from small donations (bigger donors include LinkedIn founder Reid Hoffman and former New York mayor Michael Bloomberg).

Outspent by the Republicans and at war with the world’s wealthiest person, Talarico has described his political fight as “David vs Goliath”.

Ohio

Ohio is now a red state – former president Barack Obama won it in 2008 and 2012, and then Trump won in 2016, 2020 and 2024.

This year’s Senate battle between Republican incumbent Jon Husted and former Democratic senator Sherrod Brown has also cost more than $US500 million, AdImpact said. Democrats have clung to polls showing many Ohioans believe Brown is the incumbent and have tried to portray Husted as the face of (increasingly unpopular) data centres. Both Trump and his deputy, JD Vance, have rallied for Husted, with Trump even complimenting his bottom.

“I said his ass, it’s like a pile of muscle,” he said.

Michigan

Republicans see swing-state Michigan as an opportunity to pick up a seat – and are lapping up a conflict between Democratic Senate candidate Abdul El-Sayed and the woman he defeated in an August primary, Haley Stevens. Stevens has vowed to vote for the Republican candidate Mike Rogers instead of El-Sayed after a controversial PAC ad portrayed Rogers as in thrall to Israeli interests.

El-Sayed’s team distanced itself from the ad, which critics said played up antisemitic tropes, and played down the stoush, pointing out that he had raised a record $US2.4 million in a single day. Republicans have outspent Democrats in this bitter contest, yet were behind 42 per cent to 53 per cent in recent polling. El-Sayed told 60 Minutes his opponents had spent a “third of a billion dollars just to beat me in a campaign … I don’t take money from corporations, I want to stand up to them.”

Iowa and Maine

At more than $US200 million in spending each, the next most expensive Senate campaigns are in Iowa and Maine. Federal Election Commission data shows Iowa’s Democratic candidate Josh Turek has raised $US24 million, whilst his Republican rival Ashley Hinson has raised $US14 million. Republicans have outspent their rivals in Maine, where long-time Senator Susan Collins faces Democrat candidate and logger Troy Jackson.

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