Democrat Jon Ossoff raised more than $4.7 million in the month of August, which his campaign said was the highest single-month fundraising total for any U.S. Senate contender in Georgia history.

Ossoff disclosed the fundraising total on Thursday as outside groups intensify efforts to sway the race for U.S. Sen. David Perdue’s seat.

The Senate Leadership Fund, aligned with Senate Republicans, has spent roughly $5 million to support Perdue and is expected to pour in at least another $13.5 million through the fall.

Meanwhile, the Senate Majority PAC recently announced plans to spend $7.2 million on ads supporting Ossoff during the final stretch of the race.

Ossoff, an investigative journalist, is racing to rebuild the fundraising machine that amassed more than $30 million for his 2017 special election campaign.

He previously reported amassing nearly $3 million in the month of July and out-paced Perdue in the three-month period from April to June, though the incumbent reported far more -- about $10.7 million -- in the bank.