In the race to be the next chairman of the Democratic National Committee, New York City Mayor Bill de Blasio is throwing his support behind Minnesota Rep. Keith Ellison, whose frontrunner status may soon be challenged by the potential entry into the race of Labor Sec. Tom Perez. “The Democratic Party stands at a crossroads, and needs leadership that will expand our vision to more Americans — while also intensifying our commitment to our core values. Keith Ellison is that leader,” de Blasio said in a statement provided to NBC News. The mayor of the country’s largest city has positioned himself as a national progressive leader and is the latest in a long list of liberals supporting Ellison. But de Blasio also has longstanding ties to Hillary Clinton, whose 2000 Senate campaign he managed and whom he backed in the Democratic presidential primary. In his endorsment, DeBlasio called Ellison “a unifier who worked tirelessly for both Bernie Sanders and then Hillary Clinton, he will bring the party and the grassroots together while broadening and deepening the Democratic Party’s connections to the American people.” And the mayor praised Ellison as a “grassroots organizer,” who “has delivered real results like voter turnout in his native Minnesota,” while also being a “passionate fighter for economic fairness.” Ellison, who supported Sanders in the primary, is trying to avoid turning the DNC leadership race into a rehash of the heated presidential primary. President Obama and others have encouraged Perez, who backed Clinton, to run in…more detail