Civil rights activist and writer Shaun King tweeted on Friday that he was considering endorsing Vermont Senator Bernie Sanders in the November 2016 presidential race, a potential boost to the self-described socialist among African-American voters.

King, who has been outspoken in criticizing police violence in communities of color, tweeted: “I fundamentally reject the notion that @BernieSanderscan’t win a general election. He can’t beat who? Trump? Carson? Jeb?”

Sanders has eroded much of Hillary Clinton’s lead in the race for the Democratic nomination but has struggled to gain traction with minorities, among whom Clinton and her husband, former president Bill Clinton, remain popular.

The nod from King, however, could help Sanders boost his visibility with voters of color.

King also poured cold water on the idea of a candidacy by Vice President Joe Biden, who is currently weighing a run for the White House. He highlighted Biden’s sponsorship of current prison laws and called Biden and Clinton politically “the same person. Voting for Joe on personality is why people voted for George W. Bush.”