Kemp, Georgia's secretary of state, is campaigning to a conservative base in rural parts of the state, hoping to keep the seat red after current Gov. Nathan Deal completes his two terms.
Vice President Mike Pence, left, and GOP gubernatorial candidate Brian Kemp wave to supporters at a campaign event in Dalton on November 1, 2018.
Former President Barack Obama committed his support to Abrams last week and will be headlining a rally at Moorehouse College this Friday.
Winfrey, who said she is a registered independent, has long championed Democratic Party causes and some fans earlier this year tried to encourage her to run against Republican President Donald Trump in 2020.
More than 1.5 million of the state's nearly 7 million registered voters have cast ballots already.
While Abrams has touted her experience working with Republicans as minority leader in the Georgia legislature, her positions on health care, education spending, criminal justice and gun regulations make her an unapologetic liberal.
"I am honored to have Oprah join me for uplifting and honest conversations with voters about the clear choice before us in this election and the boundless potential of Georgians", Abrams said in the statement.
"I paid to come here myself, and I approved this message, ' Winfrey said, explaining that she tracked down Abrams" cellphone number and called her to say she wanted to offer assistance in the final days of the campaign.
"I don't want to run, OK?"
He will host President Trump in Macon that day. Kemp is trying to prevent Democrats from establishing Georgia as a legitimate presidential battleground state.
Mr. Kemp had been expected to meet Stacey Abrams, the Democratic candidate, in a Sunday evening debate that was announced in September and was to be broadcast live.