Opinion polling for the United States Senate elections, 2008
Columns: Poll Source | Dates administered | Democrat: Tom Harkin | Republican: Christopher Reed | Lead Margin
Survey USA | October 28-October 29, 2008 | 61% | 35% | 26 | Rasmussen Reports | October 23, 2008 | 57% | 41% | 16 | Rasmussen Reports | September 25, 2008 | 54% | 40% | 14 | Survey USA | September 17-September 18, 2008 | 60% | 37% | 23 | Des Moines Register/ Selzer & Co | September 8-September 10, 2008 | 53% | 34% | 19 | Rasmussen Reports | August 7, 2008 | 60% | 36% | 24 | Rasmussen Reports | July 10, 2008 | 55% | 37% | 18 | Rasmussen Reports | June 10, 2008 | 53% | 37% | 16 | Research 2000 | April 21-April 23, 2008 | 59% | 20% | 39