The Republican Senate candidate from Colorado was put on the defensive Sunday after he compared being gay to the disease of alcoholism.

In a debate on Meet the Press, Buck told NBC’s David Gregory that being gay, like alcoholism, was not completely determined at birth.

GREGORY: Do you believe that being gay is a choice?

BUCK: I do.

GREGORY: Based on what?

BUCK: Based on what? I guess you can choose who your partner is.

GREGORY: You don’t think it’s something that’s determined at birth?

BUCK: I think that birth has an influence over it, like alcoholism and some other things, but I think that basically, you have a choice.

The Democratic opponent, Sen. Michael Bennet, quickly disagreed.

“I absolutely believe he’s outside the mainstream of views on this,” said Bennet.

After the debate, Buck tried to explain himself to reporters.

“I am not a biologist and I haven’t studied the issue, but that’s my opinion,” Buck said. “I wasn’t talking about being gay as a disease. I don’t think that at all and I hope that no one would be that insensitive to try to draw that…I certainly didn’t mean it that way.”

In an earlier debate, Buck had expressed support for “don’t ask, don’t tell,” saying the country shouldn’t get distracted by “lifestyle choices.”

BUCK: I do not support the repeal of Don’t Ask, Don’t Tell. I think it is a policy that makes a lot of sense. It’s not whether an individual is gay can serve in the military, the question is whether that individual can be openly gay in the military. It’s one thing to deny someone access to the military and to a career in the military, it’s another thing to — for morale purposes and other purposes — make sure that we are as homogeneous as possible in the military in moving towards the common goal of the security and the military action, as opposed to the distractions that are caused by allowing lifestyle choices to become part of the discussion.

This video is from NBC’s Meet the Press, broadcast Oct. 17, 2010.

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