Former Georgia Lt. Gov. Geoff Duncan backing Kamala Harris

Geoff Duncan, former Georgia lieutenant governor, outside the Fulton County Courthouse in Atlanta)Ben Hendren/Bloomberg via Getty Images)

Former Georgia Lt. Gov. Geoff Duncan has put his support behind Vice President Kamala Harris for the 2024 presidential race.

Duncan, an outspoken critic of former President Donald Trump, said on Twitter that he's supporting the Democratic Party to defeat the Republican nominee.

"I’m committed to beating Donald Trump. The only vehicle left for me to do that with is the Democratic Party. If that requires me to vote for, speak for, or endorse @KamalaHarris then count me in," Duncan wrote on X.

The former Republican lieutenant governor had previously said he was going to vote for Joe Biden in November, putting the blame for the Jan. 6 riot at the U.S. Capitol squarely at Trump's feet.  

In an editorial written in May, Duncan outlined what he believed should be a refocusing of efforts by the Republican Party to get back to its roots, put emphasis on congressional races and growing the party beyond its Trump era. 

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He also wrote that he is disappointed by the number of detractors who have thrown their support behind Trump, singling out U.S. Senate Minority Leader Mitch McConnell, New Hampshire Gov. Chris Sununu and former U.S. Attorney General Bill Barr. 

"Trump has shown us who he is. We should believe him. To think he is going to change at the age of 77 is beyond improbable," Duncan wrote. 

In the latest polls, Harris has been behind Trump by a small, but not insurmountable margin.