Democratic congressman Mark Udall has officially launched his campaign for the U.S. Senate. He began a four-day tour of the state Tuesday morning in Colorado Springs.
Other stops on Udall's tour Tuesday include Gunnison, Grand Junction, Craig and Denver.
Udall is campaigning for the Senate seat held by Republican Senator Wayne Allard, who is retiring. His opponent will be former congressman Bob Schaffer, who is expected to accept his party's nomination at the Colorado Republican convention on Saturday, May 31.