Plenty of polls have showed Bennet leading Romanoff narrowly. In June, SurveyUSA found that Bennet had a 17 point lead -- the only poll ever to show him with anything resembling that kind of margin. Now SurveyUSA has Romanoff ahead by several points. It's a surge...providing you ignore the numerous public polls, both internal and public, that have shown a close race for months. SurveyUSA uses automation to conduct polls, which automatically makes it suspect for many consultants and analysts. (The jury is still out for me.)
The activists I know are feeling excited about the Survey USA poll, they feel as though Romanoff has held the grassroots support all along and finally that momentum has carried their candidate to the lead. Peaking at the right time, as one friend put it.
I think getting an accurate poll of primary voters in a small state like Colorado is tough. Things seem to be pointing Romanoff's way but who really knows?