Ken Buck Leads Colorado Senate Race; Tom Tancredo Scrambles Governor's Contest

Republican Senate candidate and Tea Party favorite Ken Buck has a 49 percent to 40 percent lead among likely voters over Democratic Sen. Michael Bennet with 10 percent undecided, according to a Reuters/Ipsos poll conducted Aug. 20-22. The margin of error is 4.6 points.

Buck's margin is smaller when all registered voters are tested -- 44 percent to 40 percent with 15 percent undecided. The margin of error in this case is 4 points.

In the governor's race -- which is now a three-way -- affair, former Republican Rep. Tom Tancredo's presence as a third party candidate is throwing a big monkey wrench into Republican hopes to win the seat.

Democrat John Hickenlooper, Denver's mayor, leads Republican businessman Dan Maes by 41 percent to 33 percent among likely voters with 16 percent for Tancredo and 9 percent undecided. Hickenlooper's margin is bigger if all registered voters are surveyed.

If Tancredo were to drop out, Maes and Hickenlooper would be tied at 45 percent each with 9 percent undecided among likely voters. However, among all registered voters, Hickenlooper leads 48 percent to 38 percent with 13 percent undecided.

Polling analyst Nate Silver has observed that the "general consensus" among pollsters is that "likely voter polls are better when you're close to an election but perhaps not any better when you're months away from one and few people are tuned into politics." It being almost Labor Day, it's hard to judge on this one.

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