After much speculation about the role the Koch brothers will play in this cycle’s presidential primary, they are unlikely to get involved at all.

The day after front-runner Donald Trump expanded his lead in the Republican presidential primary, winning four of five states, wealthy conservative activists Charles and David Koch are allocating their network’s financial resources on down-ballot races. Freedom Partners Action Fund is releasing a $2 million television and digital ad buy in Ohio against former Gov. Ted Strickland who is running for the U.S. Senate seat against incumbent Republican Rob Portman.

The Kochs do not support Trump and have contemplated spending money in an effort to defeat him. Instead they have stayed out of the race as Trump continues to win states and inch closer to clinching the nomination.

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“We’ve got a strong ground game that we’ve been putting in place, and we’ve been building up our data capabilities and look forward to the general election,” James Davis, spokesman for Freedom Partners, said in a recent interview.

The ad in Ohio features a former DHL employee who lost his job when it moved to Kentucky when Strickland was governor.

“While Ohio families were struggling, Strickland pushed through about 140 fee increases amounting to at least $1.5 billion on services ranging from hospitals and garbage disposal to birth and death certificates,” a release about the ad notes.

The Koch donor network is ready to spend up to $400 million dollars in 2016 on electoral politics.

While they didn’t take a position on the primary, their favorite remaining candidate was Florida Sen. Marco Rubio. Marc Short, president of Freedom Partners left his position to be a senior adviser three weeks ago. Now that Rubio has dropped out of the race after his disappointing loss in Florida, it’s unclear if Short will return to his previous position within the Koch network.

This article first appeared on NBCNews.com.