If you’ve been following the state-by-state polls, you may have noticed an anomaly: Colorado, a historically (though sometimes narrowly) Republican-leaning state hasn’t budged from polls showing it as a dead heat a week or two before the GOP convention. One reason: there don’t seem to be new polls in the state since then.

Well, take this with whatever grain of salt you consider appropriate, but Bush campaign pollster Matthew Dowd told the Denver Post on Sunday that the campaign’s internal polls have Bush leading:

As Bush prepares to visit Colorado this week with a newly sizable lead in the national public opinion polls, Dowd is on the hunt for premature elation.

“We are winning in Colorado outside the margin of error right now,” Dowd acknowledges - meaning that the Bush lead is more than five or six points but not yet double digits - in post-convention polling in the state.

But Colorado “is a state we are going to keep a very, very close eye on,” he says. It’s not yet painted red. That is why Bush is visiting.

Dowd . . . cites two demographic changes that are altering the face of national elections in the West, threatening the president’s prospects here.

“The fastest-growing voter population in Colorado is the Hispanic population, which - while Republicans are doing better and better each year - is still a group that leans Democratic,” he says. “That is one reason it is taken from a Republican state that people used to count on in the Electoral College to now one of those states you are going to have to fight for and not take for granted.

“And two … is the growth of married women who work outside the home,” Dowd says. They lean more Democratic than stay-at-home moms.

Those factors have also helped put Nevada and Arizona on the list of battleground states, along with New Mexico.

“Nevada and New Mexico will be contested all the way until Election Day for sure. I don’t know if Colorado will stay on that list or not. It may be a state where in October we are doing fine,” he says.

John Kerry’s campaign has not yet resumed advertising in Colorado, Dowd notes hopefully, though it has promised to do so later in the fall.

But only in Arizona, Dowd says, is the Bush-Cheney campaign feeling secure. “There is a public poll there that has us up 16, and I will say that is consistent with what we are seeing,” he says.