Republican Josh Hawley brought in about $3.4 million and spent nearly $2.9 million in recent months in his bid to unseat Missouri's Democratic Sen. Claire McCaskill.
Data provided by the campaigns on Monday shows McCaskill outraised and outspent Hawley. McCaskill brought in closer to $8.5 million and spent a whopping $17.5 million between July and the end of September.
Hawley ended September with $3.5 million cash on hand compared to McCaskill's roughly $3.2 million.
The two are squaring off for the Nov. 6 election.
McCaskill's seat is considered one of the most vulnerable, and the race is attracting considerable spending by outside groups. That could help offset McCaskill's considerable financial advantage, although outside groups are also dumping money into the race in hopes of re-electing her.