As the mid-term elections in 2026 approach, affordability is considered one of the issues that voters are most concerned about. Gasoline prices, which are one of the biggest burdens on consumers, are expected to remain high until election day.

Speculators on the prediction market platform Kalshi believe that there is an 87% probability that the national average gasoline price of AAA will still be above $4 per gallon on November 3rd.

However, although they expect prices to remain above this level, they also believe that prices could fall from the current level; Kalshi only gives a 42% probability that the average price on election day will be higher than $4.25 per gallon. As of Thursday, the national average price was $4.36 per gallon.

Gasoline prices once rose to an average of $4.56 per gallon in late May, and then there was another increase at the beginning of March following the outbreak of war in Iran and the closure of the Strait of Hormuz by that country, a passage that is crucial for Middle Eastern oil exports. After that, gasoline prices dropped to $3.79 per gallon at the beginning of July, only to rise again for the rest of the summer.

Diesel prices reached a new high in September, approaching $6.53 per gallon on September 22. Since then, the price has fallen to $6.28, but traders Kalshi believe that there is a 68% probability that the price will still be above $6 per gallon on November 3.

The rise in diesel prices has a particularly significant impact on states with a large agricultural sector, such as Iowa and Kansas; states that rely on diesel for power generation, like Alaska, are also affected. All three states will face intense U.S. Senate elections in November this year.

As gasoline prices continue to remain high, the chances for Democrats to seize control of the Senate have improved. Traders at Kalshi estimate that there is a 63% probability that the party will take over control of the Senate from the Republicans.

Disclosure:CNBC has a business relationship with Kalshi, which includes customer acquisition and a small amount of equity investment.