Some potential challengers to Vice President Kamala Harris for the Democratic bid have already made it clear they would not run. However, there is some early indication that she might not be alone in seeking the nomination.West Virginia Sen. Joe Manchin, who left the party earlier this year to become an independent, is considering reregistering as a Democrat to vie for the nomination against the vice president, according to Jonathan Kott, a longtime adviser to Manchin.Manchin repeatedly irked Democrats with his independent streak but was also a lynchpin for the Biden administration’s biggest legislative accomplishments. Ahead of Biden's announcement that he was dropping his bid for re-election, Manchin, in an interview on Sunday morning with CNN's Jake Tapper, was the latest senator to call on Biden to drop his candidacy.It wasn't clear as of Sunday night if Harris would face any other challengers for the nomination. The Democratic National Committee's chair, Jaime Harrison, said in a statement that the party would “undertake a transparent and orderly process" to select "a candidate who can defeat Donald Trump in November.”Related video below: Voters ask: "what comes next?"