Kevin Brown Resigns from Graham Platner's Campaign
Brown left after learning he is expecting a baby.
Brown previously worked with Elizabeth Warren's presidential campaign.
Platner's campaign faced recent controversies including deleted Reddit posts and a controversial tattoo.
Genevieve McDonald resigned due to deleted Reddit posts linked to Platner.
Platner leads in polls with 58% support vs. Janet Mills' 24%.
Bernie Sanders endorsed Platner, while Janet Mills entered the race.
Primary contest against Susan Collins is set for next year.