05/18/2010 01:51 pm ET | Updated May 25, 2011

Ken Buck Gaining On Jane Norton, Bennet Widens Lead In Colo. Senate Race: Public Policy Polling

The latest survey from Public Policy Polling (PPP) shows a tightening Republican senate primary in Colorado, while incumbent Democrat Michael Bennet appears to be running away from his primary challenger.

The poll, which surveyed 442 likely Democratic voters and 448 likely Republican voters, found conservative underdog Ken Buck's favorability numbers surging from 21%-32% since March. His opponent, Jane Norton saw her favorability drop from 41%-34% over the same period.

The poll gave Norton a 31%-26% advantage, just within the margin for error. The Primaries will be held on August 10.

Meanwhile, on the Democratic side, Michael Bennet has expanded his lead over challenger Andrew Romanoff from 40%-34% in March to 46%-31% in May.

Read The Entire Report Below:

PPP Release CO 518