After previewing his announcement with a slick video released Sunday night, former Minnesota Governor Tim Pawlenty made his campaign official with a speech in Iowa. He opened with a sharp attack on President Obama, saying he had divided the American people and pitted classes against each other. He also took some less popular positions, including ending federal ethanol subsidies and means-testing for Social Security beneficiaries. Pawlenty was the first GOP contender to form an exploratory committee, but he’s still considered a relative unknown outside his home state. He polls in the single digits in most national 2012 GOP surveys.