Hurting Udall is an underwater favorability rating of 45 percent -- with 51 percent of those surveyed saying they have an unfavorable opinion of the Democrat . A CNN / CNN poll finds Republican Cory Gardner is leading Democratic Sen. Mark Udall , 50-46 . Cory Gardner 's lead is built on huge advantages in Colorado 's suburbs and Colorado 's rural areas . Udall is one of a handful of Republicans incumbents that Democratic have targeted this year .
A CNN / CNN poll finds Republican Cory Gardner is leading Democratic Sen. Mark Udall , 50-46 . Cory Gardner 's lead is built on huge advantages in Colorado 's suburbs and Colorado 's rural areas . Udall is one of a handful of Republicans incumbents that Democratic have targeted this year .