Defending Main Street dropped six figures to support Troy Balderson ahead of Ohio’s 12th District Republican primary to fill former Rep. Pat Tiberi’s seat.

The conservative super PAC began airing the ad Wednesday on both cable and digitally across the district.

The PAC did not disclose how much it spent on the ad, which touts that Balderson, an Ohio state senator, was endorsed by Ohio Right to Life and voted to cut taxes in the state legislature.

Tiberi’s resignation created a mad dash to fill his seat and between Democrats and Republicans, there are more than 18 candidates vying for the seat, The Associated Press reported.

Tiberi resigned to become president of the Ohio Business Roundtable despite having a massive campaign war chest.

Defending Main Street has previously sold itself as a foil to the Club for Growth and blamed the outside group for causing Republicans to lose winnable seats, allowing Democrats to win majorities in Congress.

In 2015, Defending Main Street endorsed former North Carolina Rep. Renee Ellmers in her primary against Rep. George Holding, who was backed by the Club for Growth. Ellmers would go on to lose to Holding.

Inside Elections with Nathan L. Gonzales rates Ohio’s 12th District as Likely Republican.

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