Republicans’ nearly $1 billion war chest was expected to help the party overcome a difficult political environment ahead of the US midterm elections. But despite a massive spending blitz, polling trends have barely shifted, forcing the party to divert funds from potential victories to defending vulnerable seats.
Republican groups spent more than $740 million on congressional races between Labor Day and October 14, including at least $220 million from groups linked to President Donald Trump, according to a CNBC analysis of AdImpact data. Billionaire Elon Musk has separately donated more than $276 million to Republican groups since July.
Yet Democrats continue to lead in several competitive Senate races, while the Cook Political Report with Amy Walter favours Democrats to flip the House and remain competitive in the Senate.
“Money is an amplifier, not a magic wand,” said Neil Newhouse, partner at Republican polling firm Public Opinion Strategies. “You can buy all the airtime in the world, but if the political climate is blowing 30 miles an hour in your face, ad volume alone isn’t going to turn the weather around.”
Musk's money fails to deliver a decisive advantage
Republican groups entered the final stretch with roughly $1 billion available, compared with $579 million for comparable Democratic groups, according to a CNBC analysis of Federal Election Commission filings.
Musk has contributed more than $276 million to Republican groups since July, including $158 million to the Senate Leadership Fund super PAC and more than $76 million to his America PAC. His known federal political contributions during this election cycle total roughly $366 million.
The spending comes amid an unprecedented expansion in political advertising.
However, Republican groups have struggled to translate their financial advantage into proportionate advertising exposure. Across nine key Senate battlegrounds, Republicans outspent Democrats on broadcast television by 26% through September 30 but secured only 7% more ad airings, according to CNBC's analysis.
Hilary Braseth, executive director of OpenSecrets, a nonprofit that tracks campaign spending, said, “We are watching an unprecedented concentration and scale of political influence and wealth this election cycle.”
Why political advertising is losing its punch
Late spending and higher advertising costs have limited the effectiveness of the Republican cash advantage. Candidates receive broadcasters' lowest unit rates during the final 60 days before a general election, while outside groups such as super PACs do not enjoy the same protection.
In Texas, Democrat James Talarico continued to lead Republican Ken Paxton despite more than $113 million in negative advertising targeting Talarico since the primary.
Repeated exposure to political advertising may also be delivering diminishing returns as campaigns target the same pool of undecided voters.
“When an undecided voter has already seen 20 negative ads today, the 21st ad doesn’t persuade them. It just gets tuned out,” said Michael Beckel, money in politics reform director at Issue One. “Their eyes glaze over.”
Republicans, however, argue that spending has helped prevent vulnerable candidates from falling further behind. In Texas, the party spent $121.5 million on the Senate race in September, compared with just $5.5 million over the previous three months.
“The spending hasn’t put Paxton ahead, but it kept a messy race and flawed candidate from becoming an unwinnable one,” said a Republican operative involved in the Texas Senate race, who requested anonymity.
From expanding the map to defending safe seats
The clearest indication of Republican difficulties is the shift towards defensive spending. Since September 1, the Senate Leadership Fund and affiliated groups — according to a CNBC analysis of AdImpact data — have spent or committed roughly $180 million across those three states, all of which Trump carried by double digits in 2024.
Michael Beckel said outside groups were “diverting millions into deep-red territory to build defensive moats, leaving pickup opportunities starved for cash in the final stretch.”
In North Carolina, the Senate Leadership Fund initially pledged $71 million to back Republican Michael Whatley. On 2 October, however, the group pulled most of its remaining ad reservations after spending about $32.8 million, as Democrat Roy Cooper continued to hold a double-digit lead in FiftyPlusOne’s polling average.
The same strategy is unfolding in the House, where the Congressional Leadership Fund has withdrawn support from two vulnerable Republican incumbents and shelved efforts to flip two Democratic-held seats.
The redirection points to the central problem facing Republicans: a financial advantage that once promised to expand their electoral opportunities is now being used to limit potential losses.