President Joe Biden has issued a last-minute endorsement in Ohio’s 15th Congressional District, backing Democrat Allison Russo in a Tuesday special election that could reveal hints about their party’s strength in suburban areas.

“The daughter of a union carpenter and a spouse of a combat veteran, Allison Russo knows who built America: working people and the middle class,” Biden said Monday morning in a statement Russo’s campaign shared first with NBC News. “She’s the kind of leader we need as we build back an economy that creates good-paying jobs, delivers more affordable health care, and puts middle-class families first.”

Russo, a state representative, faces Republican coal industry lobbyist Mike Carey in the race to succeed Steve Stivers, a Republican who left the seat this year for a job in the private sector. Carey is running as a devotee of former President Donald Trump, whose endorsement lifted Carey out of a crowded GOP primary last summer.