In three races alone — Ohio, Pennsylvania and Montana — more than $1 billion is projected to be spent by Nov. 5.
The race in Ohio could break the spending record for Senate races. The race in Montana will go down as the most expensive Senate race ever on a per-vote basis. And, late in the game, Democrats are sending millions more dollars to Texas, a GOP stronghold where the party has new hopes of knocking off two-term conservative stalwart Sen. Ted Cruz, an upset that could help them protect their majority.
Republicans need to pick up two seats to capture a surefire majority, and one of those — West Virginia — is all but in the bag for the GOP.
Other races are more volatile and less predictable.
For Democrats, the brutal math of this year's election cycle is forcing them to defend eight seats in tough states. Losses by established incumbents could amount to an extinction-level event for Democrats who represent reliably Republican states.
The election also will test the down-ballot strength of both parties in Wisconsin, Michigan and Pennsylvania, the premier presidential battleground states known as the Blue Wall for their relatively reliable Democratic voting history. Wins there by Republicans would dramatically alter the Senate playing field.
All told, data from political ad tracking firm AdImpact projects that more than $2.5 billion will be spent on advertising in Senate races in this two-year campaign cycle, slightly more than the 2022 total.
That includes a half-billion dollars in Ohio alone, another $340 million in Pennsylvania and $280 million in Montana, population 1.1 million, or less than one-tenth of the population of either Ohio or Pennsylvania.
