Washington(CNN) As part of a push to advance Cory Booker's presidential ambitions, a pro-Booker super PAC is launching a campaign to reach half a million black voters in four states to persuade them to back the New Jersey senator.
The voter outreach plan, shared first with CNN, is the major inaugural effort by Dream United and its founder, San Francisco lawyer and Democratic donor Steve Phillips, on Booker's behalf.
The campaign will center on South Carolina, the first contest in the 2020 Democratic nomination fight with a sizable share of African-American voters, and three other states: Georgia, Mississippi and Maryland. In 2018, Phillips-aligned groups spent nearly $10 million across those three states to influence voters in closely watched Senate races with African-American nominees.
If Booker "comes out of Iowa strong, he likely will go into South Carolina with momentum," Phillips said. His group, he said, wants to help build the groundwork for other Southern states that will follow South Carolina's February 29 primary.
Georgia, with 105 delegates at stake, will hold its primary March 24. Black voters have made up more than half the Democratic primary electorate in recent elections in the state.
If Booker does not win the Democratic presidential nomination, Phillips said he plans to deploy the voter information he collects to help the party's eventual nominee. "Democrats can't win without black voter enthusiasm, so we see this as investment in the Democrats winning back the White House," he said.
Phillips, who previously announced plans to raise $10 million to support Booker, declined to disclose how much the super PAC will spend on the voter outreach and mobilization push.
Booker's campaign said he doesn't want any super PAC help.
"Cory is building a movement powered by grassroots donations," Booker campaign spokeswoman Sabrina Singh told CNN in an email. "Cory opposes super PACs aiming to support his or anyone's candidacy for president."
Most of the two dozen candidates seeking the Democratic presidential nomination have disavowed the work of independent political groups such as Dream United -- at a time when the party's liberal activists want to limit the influence of big money in elections.
Candidates cannot accept donations from individuals that are larger than $2,800 for the primary or general election and are barred from receiving corporate funds. But super PACs face no such restrictions: They can raise and spend unlimited amounts from virtually any source as long as they act independently of the politicians they support.
"I, frankly, would defy any of the candidates to say that trying to contact and organize and mobilize black voters is a bad thing," Phillips said in a telephone interview.
Phillips and his wife, Susan Sandler, are longtime Democratic donors and political activists. In 2008, Phillips spent about $10 million to help elect then-Sen. Barack Obama to the White House, although Obama never endorsed his work. Phillips also co-founded a PAC that supported Booker's 2013 Senate bid.
So far, Booker trails his rivals in the polls. Just 3% of Democratic or Democratic-leaning independent voters backed him in a recent CNN poll. But he ramped up early in Iowa and has deployed dozens of staffers on the ground in the first caucus state.
Booker is "well positioned to come out of Iowa strong and that's what we are trying to be ready for," Phillips said.