Oklahoma Gov. Mary Fallin is emerging as President-elect Donald Trump’s leading contender for interior secretary, three people close to Trump’s transition team told POLITICO.

Fallin, a Republican who was in contention to serve as Trump’s vice president, has been the governor of Oklahoma since 2011. Before that, she served in the U.S. House. She also chaired the National Governors Association from 2013 to 2014.