Written by Elvin Choi and Ethan Mort
More than $1 billion in political advertising targeting congressional elections aired in September, making it the biggest September of the past three election cycles. But record spending isn’t the only major shift: Republicans, who were roughly even with Democrats in September 2022 and trailed them in September 2024, now account for 60% of congressional ad spending aired this month.
Aired Congressional spending totaled $589M in September 2022 and climbed to $821M in September 2024 before surpassing $1B this September. The partisan balance has shifted just as dramatically. In September 2022, spending was split nearly 50-50 between the parties. In 2024, Democratic advertisers accounted for 55% of September spending. This September, Republican advertisers account for 60%.
The Republican spending advantage is particularly apparent in the battle for the Senate. Across the nine races ranked "Toss Up" or "Lean" by Cook Political Report, Republican advertisers have outspent Democrats in all nine.
In total, Republican advertisers aired $596.8M targeting congressional elections this month, compared with $397.6M from Democratic advertisers. Spending was more evenly split in August, when Republicans aired $276.0M compared with Democrats’ $232.8M.
The biggest drivers of Republican spending in September were Senate Leadership Fund ($116.6M), Texas PAC ($77.5M), and No Going Back PAC ($68.7M).
Senate Leadership Fund aired ads across eight Senate races in September, led by Ohio ($32.1M), North Carolina ($17.3M), Michigan ($16.1M), Iowa ($15.3M), Maine ($13.1M), Alaska ($7.4M), New Hampshire ($5.0M), and Georgia ($1.0M).
No Going Back PAC, a new MAGA Inc.-linked PAC, aired $42.5M in September across six Senate races: Ohio ($12.6M), Michigan ($10.7M), North Carolina ($7.8M), New Hampshire ($5.3M), Alaska ($3.5M), and Georgia ($2.3M). The group also aired $32.4M across 25 House elections, with its highest spending in FL-25 ($5.2M), NY-03 ($4.2M), and MI-04 ($2.6M).
Texas Senate Drives a Dramatic September Shift
Texas PAC directed its entire $77.5M in September spending toward the Texas Senate race, which saw the largest month-over-month shift in aired spending.
Republican aired spending in the race increased by $134.8M from August to September, while Democratic spending increased by $18.9M. The surge has completely changed the spending context of the race.
At the end of August, Democrats held a $27.1M advantage in aired spending targeting the Texas Senate general election. As of today, Republicans hold a $61.3M aired spending advantage.
Future Reservations
Advertisers have, to date, booked nearly $1.1 billion in reservations for October and November. This spending is split fairly evenly between Senate and House contests, with $568.7M targeting Senate races and $521.2M targeting House races. Republicans maintain an overall edge in future reservations, accounting for about 56% of spending.
Republicans hold the future reservation advantage in all nine Senate races the Cook Political Report currently rates as Toss Up or Lean. However, some of those advantages are narrow in several key battlegrounds.
In Alaska, Iowa, North Carolina, and New Hampshire, Democratic future reservations nearly equal Republican bookings. While no longer considered "Toss Up" or Lean" by Cook Political, Georgia has $38.8M in future reservations, the seventh highest future reservation total as of today. Democratic advertisers lead their Republican counterparts in October and November reservations, $22.2M to $16.6M.
Kansas, recently just being shifted to "Lean R" by Cook Political Report, has seen just $3.8M in future reservations. Republicans hold a $2.6M to $1.2M advantage. Major outside groups could still reshape the spending landscape, with the Democratic flagship Senate Majority PAC reportedly considering entering the race.
The main drivers of future Senate reservations are Senate Leadership Fund ($135.4M) and WinSenate ($128.9M).
SLF’s future reservations target the same eight-state slate where it aired ads in September: Ohio ($39.5M), North Carolina ($18.6M), Michigan ($17.5M), Maine ($17.4M), Georgia ($16.0M), Iowa ($13.2M), New Hampshire ($7.9M), and Alaska ($5.2M).
WinSenate is targeting all of those states except Georgia, with a similar distribution of spending: Ohio ($38.3M), North Carolina ($21.8M), Iowa ($20.7M), Maine ($18.9M), Michigan ($16.2M), New Hampshire ($10.4M), and Alaska ($2.5M).
Texas PAC and No Going Back PAC also have sizable future bookings. Texas PAC has $47.5M prebooked in October and November, extending Republicans’ newfound spending advantage in the Lone Star State.
No Going Back PAC currently has $25.6M booked across five races: Michigan ($9.9M), New Hampshire ($6.2M), Ohio ($4.7M), Alaska ($4.5M), and Georgia ($431K).
With more than $1 billion already reserved for October and November, the September spending surge is set to carry into the final weeks of the cycle. Republicans currently hold the overall spending advantage, but several of the most competitive Senate races remain much more evenly matched as advertisers enter the final stretch before Election Day.
