Sen. Mitch McConnellAddison (Mitch) Mitchell McConnellSenate passes 0B defense bill Overnight Health Care: New GOP ObamaCare repeal bill gains momentum Overnight Finance: CBO to release limited analysis of ObamaCare repeal bill | DOJ investigates Equifax stock sales | House weighs tougher rules for banks dealing with North Korea MORE's (R-Ky.) primary challenger had about $165,000 cash on hand at the close of September. 

He received contributions from more than 2,000 donors and noted his fundraising total put him on track to match what Sen. Marco RubioMarco Antonio RubioOvernight 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 Trump bets base will stick with him on immigration MORE (R-Fla.), another conservative who orchestrated an insurgent win, raised at the same point in his campaign.

"I am extremely encouraged by the support we have received at every turn in the last couple months and am excited to see our momentum growing," Bevin said.

But McConnell, considered by Democrats one of the most vulnerable Republican incumbents up for reelection in 2014, heavily outraised Bevin, bringing in $2.27 million during the July-September period.

His campaign said he drew donations from nearly 6,000 individual donors and now has $10 million cash in the bank.