Graham Platner on Friday 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’s paperwork was received Friday by the Maine secretary of state's office.

Maine is considered a key state for control of the narrowly divided Senate, and Democrats were desperate for a candidate capable of defeating Republican Sen. Susan Collins.

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The formal withdrawal comes two days after Platner said he would quit the race, facing an allegation of sexual assault that he has denied. Maine Democrats are seeking a new nominee, and several hopefuls have already begun jockeying for position.

State law includes a provision for Democrats to replace Platner before the general election but the replacement must by named by July 27.

Just before Platner’s Wednesday announcement, more than 100 state Democratic Party committee members signed off on holding a nominating convention, in the event of his withdrawal, to choose the nominee.

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