Now, it's important to keep in mind that the mayoral candidates have done a lot of debates, and many of these debates have featured rapid-fire yes/no questions. That a candidate would misunderstand a question and give a quick, wrong answer is certainly not hard to imagine.
However, Hancock's self-described "flub" comes on the heels of some other similar unforced errors. A month ago, when asked at a debate whether he believes in evolution, he replied, "I believe in God." At another point, when the candidates were filling out a Planned Parenthood issues survey, candidate Chris Romer identified himself as "pro-choice," while Hancock called himself "pro-family planning."
A mayoral race is a relatively low information contest. The candidates' formal positions are not terribly distinct from each other -- both are mainstream Democrats -- and there are no party labels on the ballot to help voters choose between them anyway. They also both come off as pretty decent, intelligent guys with lots of important endorsements behind them. In such an environment, small, symbolic items like Hancock's recent flubs are magnified in importance as the candidates seek ways to distinguish themselves from each other and as voters try to choose between them.
The most charitable interpretation of Hancock's flubs would be that he is making some amateurish mistakes in a heated campaign -- hardly inexcusable, but still, these are mistakes his opponent is not making. Denver's largely Democratic electorate, however, would be well within its rights to interpret these events as signs that Hancock is unreliable on vital issues like abortion and science in the schools. Denver Democrats might have given former Governor Bill Ritter's pro-life stance a pass when the alternative was a Republican, but when the alternative is a pretty capable pro-choice Democrat, these voters may not be so forgiving.