Graham Platner has submitted his paperwork to formally withdraw from Maine’s U.S. Senate race, officially ending an upstart yet troubled campaign whose dissolution threatens Democrats’ pursuit of chamber control.

Platner is facing renewed pressure to drop out of the race before a Monday deadline to replace him on the ballot after he was accused of sexual assault. He denies the allegation.

As of Tuesday morning, Platner remained undecided about whether to drop out of the race and wants to see a replacement nominee who shares his vision, according to a source.

Platner has until July 13 to withdraw his bid to unseat Sen. Susan Collins (R-ME), which would give the state party until July 27 to select a new nominee.