Geoff Duncan, a Republican and former lieutenant governor of Georgia, is taking his criticism of former President Donald Trump to the Democratic National Convention.

He is a native of suburban Atlanta, a businessman and former professional baseball player, and he flirted this year with an independent candidacy for president.

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Here are six things to know about Duncan:

Then-Lieutenant Governor Geoff Duncan throws a baseball to Georgia Tech's Jamie Taylor as the last day of the legislative session begins in the Senate Chambers at the Georgia State Capitol building in Atlanta on Wednesday, March 31, 2021. (Hyosub Shin / Hyosub.Shin@ajc.com)

Credit: HYOSUB SHIN / AJC

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Credit: HYOSUB SHIN / AJC

1. Before he entered politics, Duncan was a pitcher. After graduating from Chattahoochee High School in north Fulton County, he was a student-athlete attending Georgia Tech on a baseball scholarship and studying management. He was drafted in 1996 by the Florida Marlins, now the Miami Marlins, and played six seasons in the minor leagues before shoulder surgery in 2001 ended his career. In 2021, when he was lieutenant governor, The Atlanta Journal-Constitution was on hand when he threw a baseball across the Senate chamber to a current Georgia Tech player.

2. Duncan served three terms in the Georgia House, representing a district in Forsyth County north of Atlanta before resigning his seat to run for lieutenant governor. His one term as lieutenant governor included the COVID-19 pandemic and the contentious aftermath of the 2020 presidential election. He announced in May 2021 that he wouldn’t run for a second term, choosing to focus on building a “GOP 2.0″ movement that urges fellow Republicans to envision a party beyond Trump. Along with Gov. Brian Kemp, he faced anger from Trump for disputing and debunking the then-president’s election fraud claims.

3. While he was still in government, Duncan’s national profile rose as he became a regular guest on CNN and MSNBC. He became a CNN contributor in 2023. Early this year, he was mentioned as a potential presidential candidate. Duncan met with leaders of the independent No Labels Party, was impressed and gave the idea deep consideration, he said in an interview on the “Politically Georgia” radio show and podcast. Duncan said he was encouraged by party leaders to run on a “unity” ticket to give voters an alternative to President Joe Biden and Trump. He withdrew his name from consideration just after the March presidential primary in Georgia. “For me, the math got too personally difficult,” Duncan said at the time. “Somebody just arriving on the national scene — on the fringes of the national scene … there’s still a huge gravitational pull that you’ve got to break to become a nationally known name.” (Listen to the full interview here.)

4. Just hours before Trump and 18 others were indicted in the Georgia election interference case in August 2023, Duncan testified before the Fulton County grand jury. Duncan wouldn’t tell the AJC what questions he was asked or describe any of the inner workings of the closed-door proceedings. But he called Fulton County District Attorney Fani Willis’ probe a “pivot point” in U.S. politics. Duncan’s testimony was seen as potentially important, coming from a statewide Republican official who once was closely allied with the former president. Trump and the others are charged with election interference and racketeering involving efforts to overturn the 2020 election in Georgia. Proceedings in the case are on hold over motions to have Willis removed from the case. Nine defendants argued Willis had a conflict of interest because of a romantic relationship with Nathan Wade, the outside lawyer she hired as a Trump special prosecutor. An appeals court hearing in that challenge is scheduled after Election Day.

5. Some Georgia Republican leaders want to ban Duncan from the party. His crime? Endorsing Biden and then Kamala Harris in the presidential race. After his endorsement of Harris, Georgia GOP Chair Josh McKoon sent Duncan an open letter demanding that he “cease referring to yourself as a Republican” and said the party would take actions to “protect the Republican brand” from his influence. Duncan dismissed the attack as political pandering.

6. Duncan is a contributor to the AJC, writing opinion articles about politics and issues. Here are some of his recent articles: