Oprah Winfrey has lent her star power to the Georgia Democrat aiming to become America's first black female governor in the midterm elections next week.

Winfrey, who said she is a registered independent, has long championed Democratic party causes. Earlier this year, her fans tried to encourage her to run against Donald Trump in 2020 but she said she does not want to run.

The audience cheered as Winfrey said: "I'm here today because of the men and because of the women who were lynched, who were humiliated, who were discriminated against, who were suppressed, who were repressed and oppressed ... I refuse to let their sacrifices be in vain."