Billionaire Rick Jackson was favored to win until ex-Atlanta mayor campaigned with Barack Obama and Jon Ossoff

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Keisha Lance Bottoms, the former Atlanta mayor and Democrat, won the race for Georgia governor on Tuesday in an upset for Republicans. Bottoms will become the first Black, female governor in the US.

Georgia is historically a swing state offering tight margins to the winners of statewide contests, and billionaire businessman Rick Jackson had been favored to win the race until recent days.

Lance Bottoms campaigned with Democratic senator Jon Ossoff, who also won re-election on Tuesday, as well as former president Barack Obama days before the election.

Bottoms, 56, is from Atlanta and the child of blues musician Major Lance. She worked as an attorney and served as a magistrate judge in Fulton county before first winning elected office to an Atlanta city council seat in 2009.

Jackson poured more than $100m of his personal fortune into the campaign, flooding the media with chaotic scenes from the 2020 George Floyd protests and the death of Secoriea Turner, an eight-year-old girl murdered during a street takeover by rifle-bearing gunmen.

But in a sign of tides turning against Donald Trump and Republicans as a whole, voters elected Lance Bottoms.

In the waning days of the George Floyd protests – when she was on the short list of potential vice-presidential candidates in a Biden administration – Bottoms, mayor of Atlanta at the time, announced she would not run for re-election that year.

She later joined Biden’s administration as a senior adviser, and director of the White House office of public engagement, serving until 2023.

Bottoms entered the race for Georgia governor shortly after the party’s favorite for the run, the US representative Lucy McBath, chose not to run, citing her spouse’s health problems. She went on to defeat six other candidates in the Democratic primary without a runoff.

Bottoms campaigned on issues of affordability, pledging to sign legislation expanding Medicaid under the Affordable Care Act, and to roll back restrictions on abortion access in the state.

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