Incumbent Democratic Gov. Chet Culver would lose to former Republican Gov. Terry Branstad by five percentage points if the election were held today, according to the latest Research 2000 poll.
The October poll of 600 likely voters commissioned by the liberal blog Daily Kos found Branstad bests Culver 48-43 in the hypothetical matchup, with a margin of error of plus or minus 4 percentage points.
It was the only scenario that produced a close race, as Culver polled more than 20 points higher than two other potential rivals, Republicans Bob Vander Plaats and Chris Rants.
The favorability ratings for Vander Plaats and Rants found a majority of those polled have no opinion. Culver and Branstad’s favorability ratings were almost identical, at 56 percent and 57 percent respectively.
Branstad is expected to formally enter the gubernatorial campaign Friday afternoon.
A recent Iowa Poll conducted for The Des Moines Register by Selzer & Co. Inc. last month found Culver’s approval rating to be 50 percent, compared to 70 percent for Branstad. That poll did not do a head-to-head matchup of the candidates.
A poll last month conducted by Rasmussen Reports found Culver losing to both Branstad and Vander Plaats.
The Research 2000 poll also looked at U.S. Sen. Chuck Grassley and several potential Democratic challengers looking to unseat the six-term senator in 2010.
Grassley’s favorability rating was 55 percent. In hypothetical matchups with declared candidates Bob Krause and Tom Fiegen, Grassley wins by around 20 points. When matched with two candidates rumored to be interested in entering the race – Roxanne Conlin and Christie Vilsack – Grassley wins by around 10 points.