Sen. Jeff MerkleyJeffrey (Jeff) Alan MerkleySenate Dems hold floor talk-a-thon against latest ObamaCare repeal bill Overnight Defense: Senate passes 0B defense bill | 3,000 US troops heading to Afghanistan | Two more Navy officials fired over ship collisions Senate passes 0B defense bill MORE (D-Ore.) has raised $1.2 million for his reelection campaign since May 1, bringing his second-quarter fundraising total to $1.8 million. 

It's the best quarter yet for his campaign, and the sum adds to the just over $1 million Merkley posted during the first three months of the year, bringing his total raised for the cycle to just over $2.8 million. His campaign is expected to report $3.5 million in the bank at the end of June with no debt.

Merkley faces a challenge from Republican Monica Wehby in the fall, as the freshman senator tries to hold onto his seat. Merkley has been leading in the polls, but Republicans have hoped to put the seat in play. 

Merkley has spent $1.5 million over the last two months, his campaign reports, in large part due to the aggressive ads he has been running against Wehby, negative spots that seek to link her to the national Republican Party. 

Wehby's campaign has not yet released second-quarter fundraising totals, but the Portland neurosurgeon reported raising just under $600,000 last quarter.