Republican U.S. Senator Rob Portman of Ohio says he will not run for president in 2016. He says he will run for a second term in the Senate. Portman says his decision was not affected by his support for same-sex marriage, which led some conservatives to pledge to oppose him. Portman was on the short list of Mitt Romney's potential running mates in 2012.
Portman Will Not Run For President

congress.gov