Aaron Day’s third-party campaign cost Republican Kelly Ayotte her Senate reelection bid in 2016. Now he’s trying to take his spoiler project national.

With several Senate races tight enough for an alternate candidate to make a real difference, whether they’re Libertarian or another third party, Day is looking to spend as much as $2.5 million — or perhaps less, if his effort works as designed — to cost the GOP the Senate.

Day’s strategy is simple: Use his Stark Freedom PAC to spend relatively small amounts on online ads made with AI that boost name ID for spoiler candidates, figuring he can do just enough to hand those races to the Democrats.

Republican leaders are highly skeptical of Day’s efforts, but he sees a real chance at disrupting races across the country. What’s more remarkable is how open he is about his goal of ending the Senate Republican majority.

“You call it a spoiler campaign, I call it holding Republicans accountable,” Day told Semafor in an interview. His website is equally explicit: “We fund the margin. It costs the GOP the Senate.”

Day is targeting eight states where he’s deduced that boosting third-party candidates would hurt the Republican nominee: Texas, Iowa, New Hampshire, Minnesota, South Carolina, Michigan, Ohio, and Kansas. It’s a “Moneyball” theory of modern politics, banking on a relatively small amount of cash to mess up the margins in close contests.

Nudging a third candidate’s vote share up by a couple of percentage points higher, as he explained, takes a lot less money than the obscene amount needed to actually win a race.

“People are going to be shocked after the fact at how effective this is,” Day said. “Most voters don’t know that the third-party option exists, and a lot of these candidates don’t actually have money, and they’re not allowed to participate in the debates.”

In addition to Ayotte’s 2016 New Hampshire campaign, Libertarian candidates’ support boosted former Democratic Sen. Jon Tester in his 2006 and 2012 Montana races. The effect was clear in Nevada’s 2024 Senate race, which Democrats narrowly won as nearly 5 percent of voters picked a candidate outside the two major parties.

And no one can forget Jill Stein’s Green Party spoiler effect on Hillary Clinton’s presidential chances in 2016.

It’s hard to see how giving Democrats the Senate helps advance Day’s causes — which include concerns over centralized digital currencies and government surveillance via cryptocurrency legislation. But Day says he wants to check President Donald Trump through “gridlock” and that with Democrats in charge, the crypto market structure bill and other legislation he dislikes will continue to stall.

Several Republican groups, including the National Republican Senatorial Committee and Senate Leadership Fund, declined comment.

While third-party hopefuls appreciate his support, their goals are different. Ted Brown, the Libertarian candidate in Texas, said he’s running to win, not to cost Republicans Senate control.

“I’m running to defeat the corrupt two-party system,” Brown told Semafor. “But I would say this, if the Republicans lose the Senate on November 3: The good news is, the Republicans lost control of the Senate. The bad news is, the Democrats won control of the Senate.”

Day said his model would be replicable to punish a Democratic majority in the future as well, by boosting Green Party candidates to eat into their candidates’ margins: “I actually view this, if it works, as something that can be used to hold both major parties accountable.”