 On November 13, 2010, Daines announced he would run for the U.S. Senate seat held by Jon Tester in 2012.That year, a complaint was filed with the Federal Election Commission against Daines by the Montana Democratic Party, alleging that a radio ad he had run on behalf of a pro-life organization called Common Sense Issues (CSI) was illegal campaign activity.The complaint was later dismissed as Daines had not at that time filed as a candidate for any federal office.