Gianforte does not have an opinion on the Earth's age, Flint said. Regarding Gianforte's views on evolution, Flint forwarded a comment made last year by Gianforte in which he said, "I believe young people should be taught how to think, not what to think, and a diversity of views are what should be presented."

The ad is funded by a newly formed political action committee called Montanans for Truth in Public Schools, a group whose spending was part of a state-by-state analysis given to The Associated Press by the Center for Public Integrity, a nonprofit news organization. It aired over the weekend in the Billings, Bozeman and Missoula markets.

The committee's treasurer, Adrian Cohea, said the group is concerned that Gianforte would promote teaching creationism and intelligent design alongside evolution.

"The purpose of the group is to educate the public about Ginaforte's desire to use public dollars to fund private schools that may be teaching methodologies in evolution that are at odds with scientific consensus," Cohea said.

Documents obtained by The Associated Press show the group is funded by 12 donors. Its two largest donors are Billings television broadcasting pioneer Joe Sample and Helena real estate developer Alan Nicholson.