On August 26, Public Policy Polling released an Iowa poll. For Governor, the results are: Republican incumbent Terry Branstad 48%; Democrat Jack Hatch 35%; Libertarian Lee Deakins Hieb 2%; New Independent Party Jim Hennager 2%; Iowa Party Jonathan Narcisse 1%; undecided 12%.
For U.S. Senate, for the seat of retiring Tom Harkin: Democrat Bruce Braley 41%; Republican Joni Ernst 40%; Libertarian Douglas Butzier 2%; independent Richard Stewart 2%; independent Ruth Smith 1%. Another independent candidate who is on the ballot, Bob Quast, is not mentioned, so presumably his support was below 1%. Undecided is 14%. Thanks to PoliticalWire for the link.