Bill Smith announced Wednesday he was leaving his job as Pence's chief of staff after 16 months effective May 9. Smith has been a top aide to Pence since the Republican was first elected to Congress in 2000.
Pence called Smith's contributions to his administration "incalculable" and thanked him for his service. While Smith's formal work with the governor's office is ending, he is expected to continue as a political adviser.
Pence's supporters have mentioned him as a possible White House contender in 2016. But Pence has been mum on his future plans, saying only that he's dedicated to his current job. If Pence does run, Smith would play a key role.