What are the most expensive midterm races?

The 2026 midterm elections are set to become the most expensive on record, as Republicans pour cash into battleground races to defy history and maintain control of Congress.

Political advertising spending for this year surpassed $10 billion in October, marking an all-time high, according to media tracking group AdImpact, driven by record spending in states such as Ohio, Texas, and Maine. The previous midterm spending record from 2022 was $8.9 billion.