Rick Perry, the longest-serving governor in Texas history who famously muttered "oops" after forgetting during a 2011 presidential debate the third of three federal departments he'd pledged to close, announced Monday he won't seek re-election next year to a fourth full term.

A staunch Christian conservative, proven job-creator and fierce defender of states' rights, Perry has been in office nearly 13 years, making him the nation's longest-sitting current governor.