Former Lieutenant Governor Jane Norton has opened up an even wider lead over incumbent Democrat Michael Bennet in this year’s U.S. Senate race in Colorado.

A new Rasmussen Reports telephone survey of likely voters in Colorado finds the top Republican candidate with a 12-point lead over Bennet, 49% to 37%. Three percent (3%) like some other candidate, and 11% remain undecided.

The results are little changed if Bennet is defeated in the state’s Democratic Primary by former state House Speaker Andrew Romanoff. In a match-up with Romanoff, Norton also leads by 12 points, 47% to 35%. Five percent (5%) prefer another candidate, and 14% are undecided.

This is a slight increase in Norton’s lead over Bennet from a survey last month. At that time, she was ahead of the current senator 46% to 37% and led Romanoff 45% to 34%. Those findings were virtually identical to the ones in a survey in September.

Norton’s chief GOP challengers also defeat both Bennet and Romanoff in head-to-head match-ups but by much narrower margins. They were running virtually even with the two Democrats last month.

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Former State Senator Tom Wiens now leads Bennet 44% to 38% and Romanoff 44% to 39%.

Ken Buck, a country district attorney, is ahead of Bennet 43% to 38% and essentially tied with Romanoff 40% to 39%.

In all four of these races, approximately five percent (5%) of Colorado voters prefer another candidate and 15% are undecided.

Both Democrats appear stuck for now in the mid- to upper 30s, and one possible explanation may be the continuing debate over the national health care plan, which Bennet supports. Forty-one percent (41%) of Colorado voters support the plan proposed by President Obama and congressional Democrats, while 53% oppose it. Nineteen percent (19%) strongly favor the plan, while 47% strongly oppose it. These findings are comparable to voter sentiments nationwide.

Norton captures nearly 90% of the vote of the larger group that is strongly opposed to the health care plan. Bennet and Romanoff get similar support from the group that is strongly in favor of it.

All four of the Republican candidates lead their Democratic rivals among male voters, but Norton is the lone GOP hopeful who also has a double-digit lead among women voters and among those not affiliated with either of the major political parties.

Bennet, the superintendent of the Denver public schools, was named to the Senate by Democratic Governor Bill Ritter last January to fill out the term of then-Senator Ken Salazar when he became secretary of the Interior. Bennet is now seeking a full-term of his own. But Romanoff, reportedly miffed because he wasn’t named to Salazar’s seat, has opted for a primary challenge of Bennet, viewed nationally as one of the Democrats’ most vulnerable incumbents.

With Ritter’s surprise announcement last week that he is not seeking reelection, however, Romanoff is said to be considering jumping into the gubernatorial race instead.

Both parties will hold their primaries on August 10.

Bennet is viewed very favorably by 12% of Colorado voters, while 25% view him very unfavorably. For Romanoff, very favorables total 17% and very unfavorables 15%.

Twenty-three percent (23%) have a very favorable opinion of Norton, and 17% regard her very unfavorably. Wiens is seen very favorably by seven percent (7%) and very unfavorably by 10%. Very favorables for Buck are also seven percent, while very unfavorables are eight percent (8%).

At this point in a campaign, Rasmussen Reports considers the number of people with a strong opinion more significant than the total favorable/unfavorable numbers.

Fifty-two percent (52%) of Colorado voters rate the economy as poor, and 34% say economic conditions are getting worse. Thirty-one percent (31%) believe the economy is getting better, and 27% say it is staying about the same.

Voters in the state are almost evenly divided over whether the United States is safer today than before the September 11, 2001 terrorist attacks: 41% say yes, 44% say no. This is slightly more optimistic than views nationally.

Following the Christmas Day terrorist attempt to bomb a U.S. airliner landing in Detroit, 70% say another terrorist attempt in the United States is at least somewhat likely in the next year. Of that number, 34% say it’s very likely. Those in Colorado are slightly less pessimistic about the threat of another attack than voters nationwide.

Thirty-seven percent (37%) say the government response to the terrorist attempt was good or excellent, but another 37% say it was poor. This is a bit more positive assessment of the government response than is found nationally. A solid majority (64%) believe the December incident should be investigated by military authorities as a terrorist act. Just 21% say civilian authorities should investigate it as a criminal act.

In general agreement with voters nationally, sixty-eight percent (68%) in Colorado now favor the use of full-body scanners at airport security checkpoints, while only 19% oppose their use.

Obama won Colorado over Republican John McCain in November 2008 with 54% of the vote, but just 47% of voters In the state now approve of the president’s job performance, including 32% who strongly approve. Fifty-two percent (52%) don’t like the job the president is doing, with 43% who strongly disapprove. This is roughly comparable to Obama's job approval ratings in the Rasmussen Reports daily Presidential Tracking Poll.

New data also has been released on Senate races in Arkansas, Colorado, Illinois, Connecticut, Missouri, Nevada, New Hampshire, North Dakota, Pennsylvania, Ohio, Florida, California and the special election in Massachusetts.

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