Is it possible that pollsters are underestimating the size and composition of Colorado’s electorate in the upcoming Nov. 4 — given that the state now mails ballots to its voters?

Democrats seeing incumbent Sen. Mark Udall, D-Colo., trailing in most public polls to Republican Cory Gardner certainly hope that’s the case.

And now they have data backing it up, according to a new poll of 400 Coloradoans who voted in the 2012 presidential contest but not the 2010 midterms, plus those who were recently registered.

This poll, conducted by the Democratic-leaning group Project New America, finds that 82 percent of these so-called “drop-off” voters have received a ballot in the mail. And a combined 83 percent say they’ve already voted (22 percent of them) or are planning to vote (another 61 percent).

That suggests turnout in Colorado’s upcoming Senate and gubernatorial races could be significantly higher than in past midterms — approaching the size and composition of a presidential-year electorate.

“We will concede that Republicans are more excited that Democrats,” says David Winkler of Project New America, explaining why so many “likely voter” polls show Gardner leading. “But in Colorado, they all got mailed a ballot.”

Who are these drop-off voters? They’re younger than Colorado’s 2010 voters; more of them are minorities; and they’re more likely to be Democrats.

And according to the poll, they’re backing Udall over Gardner by 14 points, 48 percent to 34 percent.

And Gov. John Hickenlooper’s margin is even wider, 49 percent to 32 percent.

In political races, it’s never a good place to be consistently trailing in the polls — it means you’re behind. And Udall is behind in Colorado.

But in this case, Project New America is …read more