Republican presidential hopeful Mitt Romney pulled one percentage point ahead of President Barack Obama among Colorado voters in a new Denver Post poll released Friday, though the two are still effectively tied.

Romney now leads Obama 48 to 47, with a four-point margin of error in the poll that surveyed 614 likely voters by cell phone and home numbers Tuesday and Wednesday. The poll was conducted by SurveyUSA for The Post.

Romney’s one-point advantage represents a small shift from The Post poll conducted five weeks ago when Obama had a one-point, 47-46, advantage.

The bump for Romney comes after the first presidential debate at the University of Denver, which even the Obama campaign admits Romney won handily.

Though there was a national enthusiasm bump for Romney — and higher poll numbers — after that debate, 83 percent of those Colorado voters polled say the debate did not change their mind, according to the Post’s poll.

Of the small group of voters who changed their mind after the first debate, however, twice as many switched to Romney as switched to Obama.

Asked about a matchup that included Libertarian presidential candidate Gary Johnson — who is on the ballot in Colorado — respondents still picked Romney over Obama by a single percentage point, or 46 to 45. Johnson took 2 percent of the vote in The Post poll, and 5 percent of voters say they are still undecided.

Beyond the top-line numbers, there wasn’t a lot of movement in whom voters trusted with the economy and who was more likeable. Slightly more people trust Romney to fix the economy and reduce the federal deficit, but voters say Obama is more in touch with the average working person.

The Colorado voters who changed their minds the most, according to the Post poll, were college-educated. Romney and Obama have switched places with those voters. Five weeks ago, Obama led this group by five points and now Romney leads it by five points.

The Post will report further information gleaned by its new presidential poll on Sunday.

Allison Sherry: 303-954-1645, asherry@denverpost.com or twitter.com/allisonsherry