In recent weeks, Barack Obama has criticized Hillary Clinton for her past support of the North American Free Trade Agreement, which created the largest free trade bloc in the world. Rhetoric aside, where do the presidential candidates really stand on trade?

An interactive web tool created by the Cato Institute may help provide the answer. The tool tracks trade-related votes between 1999 and 2008, evaluating senators and congressmen based on their support for or opposition to trade barriers and subsidies. Those who both oppose barriers and subsidies are classified as “free traders”; those who oppose barriers but favor subsidies are “internationalists”; those who favor barriers but oppose subsidies are “isolationists”; and those who favor both barriers and subsidies are “interventionists.”

Despite her husband’s rather robust free trade record, Hillary Clinton falls into the “interventionist” category. Since being elected to the Senate in 2000, she has cast only ten votes (out of 36) in favor of free trade. Obama’s record is less extensive but similarly interventionist: just four of the 13 trade votes he has cast since his election in 2004 have supported free trade.

On the Republican side, John McCain falls squarely in the “free trader” camp, with 42 votes (out of 50) in favor of free trade. Since he has only been a state politician, former Arkansas governor Mike Huckabee is not tracked by Cato’s tool.