A new Rasmussen poll of the Iowa governor's race finds Democratic Gov. Chet Culver down 26 points to former Republican Gov. Terry Branstad. Anything under 50% means an incumbent has the potential to be vulnerable, and Culver is barely polling in the 30s.

A Des Moines Register poll conducted in early February had a similar result, and just one poll this year has found Culver with at least 40% support. This survey of 500 likely voters was conducted June 14 with a margin of error of +/- 4.5%.

Branstad 57
Culver 31
Und 6

RCP rates this race Likely Republican.

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