Democrat Keisha Lance Bottoms has made U.S. history by winning the Georgia gubernatorial race, becoming the first Black woman ever elected as a state governor in United States history.

Former Atlanta Mayor Keisha Lance Bottoms won Georgia’s race for governor Tuesday, overcoming unprecedented spending by Republican billionaire Rick Jackson to become the first Black woman in U.S. history elected to lead a state government.

Her victory shattered barriers in a state that had never elected a woman or a Black person to its highest office. It also marked a stunning reversal for Republicans, who have controlled the Governor’s Mansion since Sonny Perdue toppled Democrat Roy Barnes in 2002 to become the first Republican elected governor since post-Civil War Reconstruction.

The election also marked a remarkable political comeback for Bottoms, who survived a bruising campaign that put her turbulent four-year tenure as Atlanta mayor under a microscope and tested whether Georgians trusted her with the keys to the state’s top job.

Georgia is historically a swing state, and Republican billionaire businessman Rick Jackson had been favored to win the race until recent days.

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 race, 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.