A think tank founded by GOP presidential candidate Newt Gingrich collected at least $37 million over the past eight years from major health-care companies and industry groups, offering special access to the former House speaker and other perks, according to records and interviews. The Center for Health Transformation, which opened in 2003, brought in dues of as much as $200,000 per year from insurers and other health-care firms, offering some of them “access to Newt Gingrich” and “direct Newt interaction,” according to promotional materials. The biggest funders, including firms such as AstraZeneca, Blue Cross Blue Shield and Novo Nordisk, were...