By Shaun Boyd

DENVER (CBS4)– Democratic U.S. Sen. Michael Bennet has declined to debate Republican challenger Darryl Glenn in a CBS4, KOA News Radio, Colorado Public Television 12 debate.

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It is only the second time in CBS4 history an incumbent U.S. Senator has passed on the opportunity to debate his opponent on CBS4.

Michael Bennet, Darryl Glenn and Lily Williams (credit: CBS)

Michael Bennet, Darryl Glenn and Lily Williams debate in Grand Junction earlier this month (credit: CBS)

In 2014, Democratic Sen. Mark Udall, who was locked in a close race with Republican Rep. Cory Gardner, refused to debate on our air.

But, Bennet is not in a close race.

CBS4 analyst Dick Wadhams said “I think a reflects a weak incumbent who isn’t confident in his abilities to take on a republican opponent.”

Wadhams says Bennet owes it to Coloradans to do the debate, “I’m sure he’s confident that with the millions of dollars he has in the bank and with the way the polls look right now that he doesn’t need to do this debate. But what does that say about Senator Bennet and his commitment to talking about the issues to all Coloradans? I think says a lot.”

Just two weeks ago, the spokesman for the Colorado Democratic Party took Glenn to task for pulling out of the Denver Post debate saying, “He is depriving Coloradans an important opportunity to hear from the two candidates.”

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Bennet’s communications director, Andrew Zucker, would not explain the reasons behind the campaign’s decision.

He released a statement instead attacking Bennet’s opponent, “Darryl Glenn never engaged with our campaign to have a substantive conversation about debates and has instead blacklisted Colorado news reporters and become the first Senate candidate this millennium to refuse to do the traditional Denver Post debate. At this point we are moving forward with our campaign schedule and look forward to the remaining televised debate and joint appearances that have already been scheduled.”

Glenn told CBS4 Bennet is scared after the first debate exposed his vulnerabilities, “and he doubled down on support for the Iran nuclear deal and he continued to support the Affordable Care Act along with the EPA regulations and he did not receive a favorable response and he realizes if he’s going to sit across table from me he’s going to have to address those head on.”

Colorado’s Republican Party chair said Bennet is “trying to run out the clock and avoid voters.”

Steve House says, “After Bennet’s lackluster defense of his extremely partisan record in Grand Junction, his campaign has clearly calculated they need to limit Bennet’s exposure before Coloradans. It’s a shame Michael Bennet has robbed the people of Colorado of what should be a fair opportunity to hear from both candidates at a critical juncture in the Senate race.”

CBS4 analyst Penfield Tate says both candidates have let voters down, “You’ve got both candidates now have declined one debate opportunity for one reason or another so they’re both probably held in equal esteem, equal fault with the voters.”

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Shaun Boyd is CBS4’s political specialist. She’s a veteran reporter with more than 25 years of experience. Follow her on Twitter @cbs4shaun.