A presidential election prediction model developed by two University of Colorado professors points to a big win for GOP presidential contender Mitt Romney in November.

The model, the only of its kind to use more than one state-level economic indicator, has correctly predicted the winner of every presidential election since 1980.

It predicts Romney winning the electoral college by a 320-218 margin and winning 52.9 percent of the popular vote when only the two major parties’ candidates are considered, the Associated Press reported Thursday.

Romney, it concluded, will win every state currently considered by pollsters to be a swing state, including Ohio, Pennsylvania, Wisconsin, Florida, Virginia, Colorado, New Hampshire and North Carolina.

The model even predicts Romney will win Minnesota and Maine’s Second Congressional District, the electoral votes of which most pollsters consider to be “safe” for President Obama. Nevada and Iowa are the only swing states it assigns to Obama.

“Based on our forecasting model, it becomes clear that the president is in electoral trouble,” explained Kenneth Bickers, a political science professor at the University of Colorado-Boulder who developed the prediction model with Michael Berry of University of Colorado-Denver.

“The apparent advantage of being a Democratic candidate and holding the White House disappears,” Berry noted, “when the national unemployment rate hits 5.6 percent. The incumbency advantage enjoyed by President Obama, though statistically significant, is not great enough to offset high rates of unemployment currently experienced in many of the states.”

Bickers said large issues like the economy and the country’s overall direction tend to determine presidential elections. Computerized prediction models “suggest that presidential elections are about big things and the stewardship of the national economy,” he said. “It’s not about gaffes, political commercials or day-to-day campaign tactics. I find that heartening for our democracy.”

Bickers and Berry cautioned, however, that their model used economic data from June, 2012. They intend to update their calculations when new data become available in September.

And many swing states showed close enough to a 50-50 split that factors other than the economy could tilt them in the opposite direction. Bicker and Berry also did not factor in third party candidates, such as Libertarian presidential nominee Gary Johnson, who Public Policy Polling, a Democratic-affiliated polling firm, has noted could significantly diminish Obama’s chances of winning New Mexico.

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