WASHINGTON — Beto O’Rourke hasn’t made up his mind about a possible presidential run in 2020, but behind the scenes he’s speaking to potential kingmakers among a constituency whose support he’ll need in a Democratic primary: African-Americans.

In the last two weeks, the soon-to-be-former Texas congressmen met with former President Barack Obama at his Washington office, a source familiar with the meeting confirmed to NBC News, and spoke by phone with the Rev. Al Sharpton and fellow 2018 progressive darling Andrew Gillum. The O’Rourke-Obama meeting was first reported by The Washington Post.

The phone call with Gillum has not been previously reported, and was described to NBC News by two sources told of it later. One source, granted anonymity to describe a private conversation, said the pair discussed their mutual preference that someone “young and unapologetically progressive” lead the Democratic Party going forward. The two men had never spoken before, according to the source, and it was Gillum who reached out to O’Rourke to arrange the call.

Gillum, who narrowly lost his bid for Florida governor, also met with Obama recently and has been sounding out key Democrats about his political future.

Sharpton, an MSNBC anchor and civil rights activist, told NBC News that he invited O’Rourke to a Martin Luther King Jr event in January, and that O’Rourke called him on Friday to say he could not attend but wanted to keep lines of communication open.

Sharpton said O’Rourke offered no clues about his possible presidential intentions, which O’Rourke has been re-thinking. After seemingly closing the door on a White House run during his Senate campaign, he re-opened it late last month, saying he had ”made a decision to not rule anything out.”

African-American voters, long a bedrock constituency for the Democratic Party, has only seen its political clout enhanced by recent changes in the presidential primary calendar that moved more Southern states with significant black populations earlier in the process.

Hillary Clinton’s entire margin of victory in the 2016 nomination fight with Sen. Bernie Sanders came thanks to lopsided delegate hauls in key Southern races. She won 74 percent of the primary vote in South Carolina, the first Southern primary, and posted similar tallies Mississippi, Louisiana, Georgia, South Carolina and Alabama, all of whom held their 2016 primaries as part of a two-week sprint after Super Tuesday.

Kamala Harris and Cory Booker, both African-Americans senators who are considered among the top tier of potential candidates, both campaigned aggressively in Southern states ahead of the midterm elections — including for Gillum.