It was a unique race with an incumbent Democratic governor running against a former four-term Republican governor; a race in which both candidates were well-known and ran well-financed campaigns. But rather than national trends in which the Republican Party gained a historic 60 seats in the U.S. House of Representatives and took control of two-thirds of the nation’s governorships, factors internal to the state of Iowa shaped the outcome of the 2010 election. Chet Culver, Iowa’s incumbent governor, was held accountable not only for a poor state economy but also the decision by Iowa’s Supreme Court to legalize legal same-sex marriage the previous year. Culver also faced an opponent with considerable fundraising prowess. The result was a loss to Republican challenger Terry Branstad by 10 percentage points on Election Day.

In gubernatorial elections, incumbents typically have many advantages over challengers, including more money. Gubernatorial challenger Branstad was unique in his ability to raise more money than his incumbent challenger, Culver, in large part because of individual campaign contributions.

Culver began the general election campaign with low approval numbers, and there was little improvement over the course of the campaign; Branstad, however, out-polled Culver by up to 20 percentage points. Low approval of Culver led to fewer donations than if he were more popular, and more spending does little to change the minds of voters with regard to unpopular governors.

Branstad, however, had high approval ratings throughout the campaign, and he was able to translate this into more money and more votes. Branstad raised much more than Culver and displayed much broader public support by attracting three times the number of individual donors.

Culver governed during the worst economic crisis since the Great Depression and was responsible for unpopular across-the-board cuts in state government spending. Research shows that governors, as state executives, are held accountable for perceived state economic conditions. Given the poor economic health of the United States, as well as Iowa specifically, the 2010 governor’s race may have been decided by retrospective economic evaluations. In short, Culver may have been held accountable for the poor economic conditions of the state.

The headline story of the Iowa 2010 elections was not the dueling governors but that Iowans had overwhelmingly voted to not retain three Supreme Court judges who had ruled in a unanimous decision to legalize same-sex marriage one year prior. Never in the 60 years since retention elections were instituted in the state had the judges not been retained. Hundreds of thousands of dollars in external funds from religious organizations were diverted to Iowa and 527s including the National Organization of Marriage to air negative campaign ads about same-sex marriage and the Iowa Supreme Court. Polls reveal many turned out to vote in the midterm election because of the judicial-retention elections, not the candidates for elected office. The judicial elections became a referendum, akin to the politics of direct democracy, on the court’s ruling to legalize gay marriage.

Support and opposition to the Supreme Court judges divided along partisan lines. Poll data provide evidence that Iowa voters were informed of the importance of the judicial-retention elections and had tied the vote to the issue of same-sex marriage.

These are three stories of how challenger Branstad was able to unseat incumbent Culver to lead the state of Iowa. The first was based on the Branstad’s fundraising, the second the poor economy, and the third the unique judicial-retention elections that became a referendum on same-sex marriage.

We provide some evidence that all three explanations have validity. However, the explanations are rooted in unique Iowa experiences, rather than nationwide trends. Iowa remains a battleground state, and either political party could win the hearts and souls of Iowans in 2012. As the presidential primaries begin with the Iowa caucuses in January 2012, Iowa will once again be a national stage for testing the presidential candidates for both parties.

Caroline Tolbert is aprofessor of political science at the University of Iowa and a contributing author to a new book, Pendulum Swing, edited by University of Virginia Professor Larry J. Sabato, from which this article is adapted. Amanda Keller is a UI graduate student who assisted Tolbert with this piece.