The race to replace a term-limited Nathan Deal in 2018 is well underway, and it's shaping up to be a crowded and costly contest. So far, we have five leading Republicans and two Democrats in the race. Here are a few things to know about each:

Republicans

Lt. Gov. Casey Cagle

Details: The Gainesville Republican was first elected to the state Senate in 1994 at the age of 28, becoming the youngest member of the chamber. He scored an upset victory against Ralph Reed in 2006 for Georgia's No. 2 job, and has twice won re-election bids by hefty margins. He launched a 2010 bid for governor before dropping out of the race, and he's since written a book on education, championed a mix of conservative-friendly school initiatives and has tried to establish himself as the presumptive frontrunner after Donald Trump's victory. He seems determined not to get out-flanked on the right; although he rarely mentions Trump on the campaign trail, he's embraced conservative priorities such as the "religious liberty" measure.

Status: He's in, and he filed formal paperwork to run in April. His campaign kickoff was held at the end of the month.

Secretary of State Brian Kemp

Details: A former state senator, the Athens Republican was appointed by Gov. Sonny Perdue as the state's top elections official in 2010 and won his first of two four-year terms later that year. Kemp, 53, has tried to score political points by railing against left-leaning groups that accused his office of voter suppression and has made a strong play for the rural counties that helped propel President Donald Trump to victory in 2016. His campaign mantra: "Putting Georgia First." His opponents hope he could be hobbled by the 2015 accidental disclosure of voter data.

Status: He is in the race, making the announcement on March 31.

State Sen. Hunter Hill

Details: A state senator who represents a Buckhead-based district, Hill is a U.S. Army veteran who carved out a relatively low-profile in the Georgia Senate. He staked out a reliably conservative voting record in the chamber, which left him vulnerable in his fast-changing district: He only narrowly defeated a Democratic challenger in 2016. He hopes to fare better with a statewide campaign, which he said will center on a promise for "more efficient and effective state government."

Status: He's in, and announced his candidacy in late April.

Businessman Clay Tippins

Details: Tippins is trying to cast himself as the leading outsider in a crowded GOP contest packed with candidates with elected experience. The 44-year-old tech executive is a former Navy SEAL who was captain of Stanford's swim team. He enters the race as a virtual blank slate, with no public profile or voting record, little name recognition and without the huge trove of cash needed to finance his campaign on his own. But Tippins’ supporters hope his outsider status appeals to conservatives who turned to newcomers Donald Trump and David Perdue in past Georgia votes.

Status: He filed paperwork to run in mid-September.

State Sen. Michael Williams

Details: The Cumming Republican and businessman owned a chain of haircut franchises before he was elected on an outsider's platform in 2014, and was the first state elected official to endorse Trump. He eyed the Secretary of State's office before Trump's win but decided instead to run for higher office. His campaign has been characterized by bold statements and harsh accusations about his rivals, such as his claim that Cagle's allies offered him a key committee assignment to stay out of the race. An early press conference he staged aiming to embarrass Cagle fizzled.

Status: He is running and announced his campaign on June 1.

Also: Former educator Marc Alan Urbach of Dunwoody is running as a Republican. He also ran for president.

Republican candidates who have ruled themselves out:

Georgia strategist Nick Ayers. Former Rep. Lynn Westmoreland.  State Sen. Burt Jones. House Speaker David Ralston.  Former Gov. Sonny Perdue. State Sen. Josh McKoon. U.S. Sen. David Perdue.

Democrats

Former House Minority Leader Stacey Abrams

Details: A darling of the national media, the 43-year-old Atlanta Democrat is often seen as a leading voice for the party in the South. As the head of the Democratic caucus in the state House, she's known to work with Republicans rather than outright oppose GOP initiatives. The voter registration group she founded, the New Georgia Project, aims to register hundreds of thousands of left-leaning voters; it has come under scrutiny for its tactics and results.

Status: She announced her campaign on June 3.

State Rep. Stacey Evans

Details: The Smyrna attorney is the go-to Democrat in the House on the push to restore funding that had been cut from the state's HOPE scholarship program. A Ringgold native, she is the first in her family to graduate from college, and she used her share in a massive whistleblower settlement she handled to create a scholarship for first-generation graduates at the University of Georgia's law school. She was shouted off the stage at a progressive conference by protesters chanting "support black women," hinting at the divide that has Democrats worried.

Status: She announced she was in the race on May 25.

Democratic candidates that have ruled themselves out:

Former state Sen. Jason Carter.  Former acting U.S. Attorney General Sally YatesAtlanta Mayor Kasim Reed.  Former Rep. John Barrow.  Columbus Mayor Teresa Tomlinson.

Libertarian Doug Craig

Details: A veteran of the Gulf War who operated nuclear reactors for the U.S. Navy, Craig runs a sheet-metal fabricator shop in Atlanta's southside. As former chair of Georgia's Libertarian Party, he backed the failed candidacies of Andrew Hunt for governor and Amanda Swafford for Senate.

Status: He's running . He became the first candidate to formally jump in the race in August 2015, promising to be a third-party contender with a "strong message, not a watered down message."