Republican Geoff Duncan has filed paperwork setting the stage for a run for lieutenant governor.

The state legislator from Cumming hopes to succeed Lt. Gov. Casey Cagle, who is planning to run for governor.

Duncan has forged an unconventional path to office. A former Georgia Tech standout, Duncan pitched six seasons in the Miami Marlins minor league system before reconstructive shoulder surgery in 2001 forced him to end his career. He moved to the Atlanta suburbs with his wife to start a marketing company and now runs a healthcare firm.

He decided to run for office in 2011, making a play for a newly-created House district drawn that seemed designed for former Rep. Tom Knox’s comeback. He won the seat in 2012 by 55 votes, and since taking office has a few wins under his hat.

His proposal to require all bar bouncers to be 21 or older – dubbed Michael’s Law after the death last year of an 18-year-old bar staffer – passed with little opposition.

He also backed legislation that allows residents or corporations to get a state tax credit for donating money to a rural hospital, a measure pitched as a way to help struggling rural facilities. It passed despite criticism from some Democrats, although top lawmakers are worried some of the funds could be siphoned to consultants.

He's entering what could be a crowded field for Georgia's No. 2 job. Senate President Pro Tem David Shafer, Senate Majority Leader Bill Cowsert and state Sen. Butch Miller are considered potential candidates. So are state Sens. Burt Jones and Hunter Hill. And Democratic state Rep. Stacey Evans is among the potential contenders across the aisle.