In Georgia, Iowa, Massachusetts and North Carolina, the midterm elections proved that candidates shouldn't be afraid to talk about the benefits of trade. They also demonstrated that candidates tempted to employ protectionist scare tactics in their campaigns should think twice.

In Iowa, Republican Senate candidate Joni Ernst's campaign argued: "Congressman [Bruce] Braley's Anti-Free Trade Votes are Bad for Iowa Farmers." According to Politico:

Iowa Republicans, in one of the tightest Senate races in the country, are trying to capitalize on Democratic Rep. Bruce Braley's record of voting against trade agreements to help hand their candidate, Joni Ernst, the victory. Braley, whose state is heavily dependent on farm exports, voted against free trade pacts with South Korea, Colombia and Panama in 2011, even after President Barack Obama's administration re-negotiated several provisions to round up more Democratic support. "The South Korean trade deal was huge," Agriculture Secretary Bill Northey told POLITICO in an interview. "Everyone knew it was a clear, clear win for agriculture and it would have been a terrible not to have it. For him to vote against that I just think is a major red flag."

Ernst defeated Braley, 52.2 percent to 43.7 percent.

In North Carolina's Senate race, Democratic incumbent Kay Hagan said: "Unfair trade agreements have contributed to the loss of more than 286,000 North Carolina manufacturing jobs in the last decade — the fourth-largest decline in the nation. It is time we start protecting jobs here at home." Her campaign spokesman added: "Kay opposed trade agreements that ship North Carolina jobs overseas because she will always put North Carolina jobs first."

Her Republican opponent, Thom Tillis, disagreed: "As agriculture exports increase, Thom believes we must promote policies that make trade with other nations free and efficient in order to stimulate our economy and allow North Carolina farmers and ranchers to expand their businesses."

Tillis defeated Hagan, 49.0 percent to 47.3 percent.

In Massachusetts, the Democratic Governors Association released an ad attacking Republican gubernatorial candidate Charlie Baker: "Baker won the Outsourcing Excellence Award at the 'Oscars of Outsourcing' for his work destroying jobs here at home." Baker replied that outsourcing some jobs to India allowed Massachusetts insurer Harvard Pilgrim to save thousands of jobs at home. Former Massachusetts Attorney General Thomas F. Reilly (D) called the outsourcing attacks "exactly the kind of nonsense that drives people away from the political process."

Baker defeated Democrat Martha Coakley, 48.5 percent to 46.6 percent.

In Georgia, Democratic senatorial hopeful Michelle Nunn attempted to smear her Republican opponent David Perdue for outsourcing jobs to other countries: "David Perdue, he's not for you," her ad proclaimed. When a reporter asked Perdue to defend his use of outsourcing, he replied: "Defend it? I'm proud of it. ... It's the lack of understanding of the free enterprise system that I'm running against here."

Perdue beat Nunn, 53.0 percent to 45.1 percent.

After the Massachusetts and Georgia elections, Computerworld reported: "Offshore outsourcing fails as election issue: A longtime Democratic bludgeon isn't enough to move needle." In contrast, candidates who embraced the benefits of trade, like Joni Ernst and Thom Tillis, emerged victorious.

Promoting free trade is good economics, too. A comparison of trade policy around the world, developed by the Heritage Foundation and The Wall Street Journal in the annual Index of Economic Freedom, shows a strong correlation between trade freedom and prosperity. Washington Post columnist Steven Pearlstein observed that outsourcing saves U.S. businesses and consumers billions of dollars each year:

Those savings and those extra profits aren't put under the mattress. Most of it is spent or invested in the United States in ways that are hard to track but have surely created hundreds of thousands of jobs in other companies and other industries. Those who hold those jobs would have no reason to know that they are beneficiaries of the process of outsourcing and globalization. But in a very real sense, they are.

Most economists agree that criticizing trade is bad policy. Last week's election results suggest it may be bad politics, too.

 - Bryan Riley is the Heritage Foundation's Jay Van Andel Senior Policy Analyst in Trade Policy.