Similar patterns play out with respect to education. A study co-authored by Houston found that U.S. presidents tend to polarize public opinion every time they take a highly publicized stand on issues like standardized testing or school vouchers. Though few voters hold strong opinions on such questions, they quickly take cues based on their appraisal of the president; only in cases when the president’s position cut against the traditional views associated with his party — such as Barack Obama’s support for charter schools and teacher merit pay — did his endorsement drive support for a given policy.