"This obstruction of our work is just so egregious," Sen. Udall told CPR News.
In an attempt to woo female voters, Democrats have long chided Republican candidates on the issues of abortion and birth control. One group says that’s a losing strategy.
U.S. Sen. Mark Udall, who is locked in a bitter re-election battle with Republican U.S. Rep. Cory Gardner, did not join Obama on stage or at a later fundraiser.
Colorado's Senate seat could be the key to which party controls Congress next year.
Senator Mark Udall traveled to Chaffee County Tuesday to unveil new proposed legislation that declares Browns Canyon a national monument and wilderness area.