Lt. Gov. Casey Cagle took an initial step Monday to run for governor by filing paperwork to run for the seat in 2018.

The Republican has plotted for years to run for the state's highest office, and a formal announcement is expected within a month.

Cagle is the presumptive Republican front-runner in what could be a crowded field to succeed a term-limited Nathan Deal. Secretary of State Brian Kemp is already in the race, and a cast of current and former lawmakers - along with an "outsider" or two - are considering entering the contest.

Democrats are gearing up for a chance to flip the seat for the first time since 2002. House Minority Leader Stacey Abrams is seen as a lock to join the race and others, including state Rep. Stacey Evans and former state Sen. Jason Carter, are exploring a run.

A Gainesville native, Cagle was elected to the Georgia Senate in 1994 at the age of 28 when he upset a Democratic incumbent. He launched what was considered a long-shot bid in 2006 for lieutenant governor against Ralph Reed, a former Christian Coalition leader with a national profile. His win sidelined Reed's political career and was the first of Cagle's three statewide victories.

But he's had his eye on a governor run for about a decade. He filed paperwork in 2008 to launch a bid for the job in 2010 and he raised more than $1.4 million for his campaign. He dropped out in April 2009, citing problems with his back.

This time around, he and his supporters have indicated there's no turning back.

He's traveled the state in the runup to this year's legislative session, collecting IOUs, hiring staff and lining up commitments. He wrote a book about education policy that published last year, and he's tried to smooth ties with powerful business groups about a "religious liberty" proposal that he initially supported. And he's raised more than $500,000 in his lieutenant governor's account since winning another term, even though most of the Capitol donors knew he planned a gubernatorial run.

His campaign is to be chaired by Charles Tarbutton, a Sandersville rail executive whose family has ties to Deal, Zell Miller and other successful gubernatorial candidates stretching back the last half-century. It's a sign that Cagle's bid has early support from one of the most well-connected political networks in the state.

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