Dan Koh holds a commanding lead in the MA-06 Democratic primary market due to his dominant fundraising edge—over $3.5 million raised—and a growing list of endorsements from local officials, unions, and groups such as End Citizens United. The open seat, created after incumbent Seth Moulton launched a Senate bid, has drawn a crowded field, yet Koh’s early ballot qualification, broad donor base across the district, and prior congressional experience have consolidated trader support. Recent internal polls show a fragmented race with high undecided numbers, but Koh’s resource advantage and establishment backing explain the wide gap over challengers like Tram Nguyen, who trails in cash and visibility. The September 1 primary remains months away, leaving room for shifts from further endorsements or campaign developments.