Democrat Graham Platner filed paperwork Friday to officially remove his name from the ballot, ending his tumultuous bid to unseat Republican Sen. Susan Collins in Maine. Why it matters: Platner's exit ahead of the Monday deadline clears the way for Democrats to name a replacement candidate in a race that is critical to their effort to win a Senate majority in November. Platner's campaign posted a copy of the letter it sent to Maine's Secretary of State withdrawing from the race to X on Friday