2018 election Duncan announced he would run for lieutenant governor of Georgia on April 10, 2017. He resigned from the Georgia House in September 2017 to focus on running for lieutenant governor in 2018. He was described as an "underdog" candidate against
David Shafer, who had served as president pro tempore of the
Georgia State Senate. On May 22, 2018, Shafer received 48.9% of the vote in the Republican primary with Duncan coming in second place with 26.6%. Because no candidate received a majority of votes, the election then went to a runoff held on July 24. Duncan acknowledged that he faced an uphill battle against Shafer in the runoff election. On July 24, Duncan, previously considered a longshot candidate defeated Shafer with 50.16% of the vote. His victory was described as an upset by
The Atlanta Journal-Constitution. He defeated Democratic nominee Sarah Riggs Amico in the
general election, receiving nearly 52% of the vote and avoiding another runoff.
Tenure Duncan was inaugurated lieutenant governor on January 14, 2019. As lieutenant governor, Duncan highlighted efforts by the Kemp administration on healthcare policy, and stated his wish for Georgia to become the "technology capital of the East Coast". in 2019.|leftOn December 6, 2020, Duncan and
Governor Brian Kemp put out a joint statement explaining that calling a joint session of the
Georgia General Assembly to appoint their own electors to send to the
United States Electoral College would be unconstitutional. Following
unsuccessful efforts to overturn the election of Democratic candidate Joe Biden in the 2020 presidential election, in March 2021 Georgia Republicans enacted the controversial
Election Integrity Act of 2021 that imposed new restrictions on voting. Days later, Duncan said during a CNN interview that momentum for the legislation grew from "the fallout from the ten weeks of
misinformation that flew in from former President
Donald Trump. I went back over the weekend to really look at where this really started to gain momentum in the legislature, and it was when
Rudy Giuliani showed up in a couple of committee rooms and spent hours spreading misinformation and sowing doubt across, you know, hours of testimony." In April 2021, Duncan's chief of staff stated that he was unlikely to run for a second term, after he openly contradicted false claims of election fraud in the 2020 presidential election. His chief of staff added that Duncan had yet to make a final decision about whether to
run again in 2022. On May 17, 2021, Duncan announced that he would not be seeking a second term. An October 2021 trip to
New Hampshire to promote his book
GOP 2.0, which outlines plans for a post-Trump future for the Republican Party, fueled speculation in his home state that Duncan may be positioning himself to run for president in
2024. Duncan said he did not vote for either
Raphael Warnock or
Herschel Walker in the
2022 U.S. Senate election. == Post-lieutenant governor career ==