Sept 19 (Reuters) - U.S. Democratic presidential

candidate Kamala Harris will join celebrity billionaire Oprah

Winfrey for an online event with grassroots groups on Thursday

to rally support in battleground states.

The "Unite for America" event, co-hosted by Winfrey and

activist group Win with Black Women, aims to register people to

vote and bolster Harris in states such as Pennsylvania, Georgia

and Michigan that are set to decide the Nov. 5 election.

Harris and Winfrey will livestream the 8 p.m. EDT (0000

GMT) event on social media including Instagram and TikTok from

Michigan, where Harris has been campaigning in the Detroit area,

local press reported.

Dozens of grassroots groups including Latinas for

Harris, Win With Black Men and Republicans for Harris are

participating. Win with Black Women campaigns for Black women

to win elected offices. Harris is Black and has South Asian

heritage.

The groups, which rallied around Harris since she entered

the race in July, have helped raise more than $20 million for

her campaign, a Unite for America press release said.

"What is essential to me is getting people motivated to

vote, and ensuring everyone makes a plan not only for

themselves, but for their families and friends," Winfrey, a

businesswoman, philanthropist and former TV host, said in a

statement.

In a recent Reuters poll, Harris led her Republican opponent

Donald Trump 47% to 42%.

Harris was ahead in the battleground states of Michigan,

Pennsylvania, Wisconsin, Nevada and North Carolina, while Trump

had greater support in Georgia, according to polling averages

from aggregator FiveThirtyEight. They are tied in Arizona.

Trump on Thursday will participate in a Washington event on

fighting antisemitism and address the Israeli-American Council

Summit.

Hours after President Joe Biden dropped out and endorsed

Harris to be the Democratic candidate, 90,000 Black women joined

a call held by Win with Black Women that raised $1.5 million in

three hours, the press release said.

In August, Winfrey spoke at the Democratic National

Convention in Chicago to press the case for Harris.

"I'm calling on all you independents and all you undecided,"

Winfrey said then, describing herself as an independent voter.

"Decency and respect are on the ballot in 2024."