Sen. Brian Schatz (D-Hawaii) has continued to outraise his primary rival, Rep. Colleen Hanabusa (D-Hawaii).

Schatz raised $600,000 in the first fundraising quarter, topping the $430,000 Hanabusa brought in. He had $2.4 million in the bank to Hanabusa's $1 million.

That cash edge has allowed Schatz to go up early on the air while Hanabusa has stayed quiet ahead of the August primary. He's already had two television spots, one featuring his family and touting his support for Social Security and the other calling for equal pay for women.

Schatz, who was appointed to the Senate in late 2012, has the backing of President Obama, the Democratic Senatorial Campaign Committee and the League of Conservation Voters, while Hanabusa is backed by EMILY's List.