The 2008 Iowa Senate election were held on November 4, 2008. The Senate seats for the twenty-five even-numbered districts were up for election. Senate terms are staggered such that half the membership is elected every two years, with each Senators serving a four-year term. Prior to the election, the Democrats were in the majority - marking the first time in 42 years that the Democrats had controlled both branches of the Iowa General Assembly and the Governor's Office. They expanded this majority by two seats in the 2008 elections.