A former U.S. Attorney for Kansas is considering a run for the Senate.

Barry Grissom says he’s considering running in 2020 as a Democrat against incumbent Republican Kansas Senator Pat Roberts.

Grissom, who was appointed by then-President Barack Obama as U.S. Attorney for Kansas in 2010, says he has no timetable on when he will make a decision to challenge Roberts.

Grissom currently works as senior vice president of global policy and general counsel for the Las Vegas-based Electrum Partners, which is a venture capital firm that invests in medical marijuana.