ROCHESTER — The co-chairman of a Minnesota county Republican Party says he’s resigning from his position because Donald Trump has emerged as the GOP’s presumptive presidential nominee.

Dave Thul has led Steele County Republicans for eight years. Thul tells KTTC-TV he initially thought Trump’s campaign was a joke or an ego trip. But, now that celebrity businessman has emerged as the probable nominee, Thul thought it was time to tender his resignation.

Thul and the group, Conservatives for Candidates of Character, plan to introduce a measure at the state convention in Duluth Friday to stop the party from spending money on Trump’s campaign.