In second among the big-name contenders is businessman Nate Morris, who launched his campaign with a $3 million loan to himself. The latest data show Morris with $1.1 million in his war chest.
Former Kentucky Attorney General Daniel Cameron has roughly $630,000 in the bank.
While Cameron trails his opponents, he continues to show a steady lead in polls -- though Barr's campaign contends he's gaining on the one-time gubernatorial candidate.
The three Senate contenders are all backed by Political Action Committees, which are busy airing attack ads as the race continues to take shape.