Rising gas prices could shape the midterms: Here's where fuel costs stand in key states.

After nearly 100 consecutive days of falling gas prices, fuel costs have spiked in recent weeks.

This time, the price increase coincides with the lead up to the midterm elections — and the trend could determine which party gains control of Congress.

The approval rating of President Joe Biden — an indicator of Democrat's election prospects — has tracked closely with gas prices. In conjunction with a monthslong fall in prices from their summer peak, Biden's approval surged.

Since the increase in prices took hold two weeks ago, when OPEC+ announced a cut in oil output, disapproval of President Joe Biden has risen 1.1 percentage points, according to FiveThirtyEight.

On Wednesday, Biden announced moves that aim to address the oil supply shortage behind the cost spike, including a scheduled release of millions of barrels of oil from the nation's Strategic Petroleum Reserve, or SPR.

But the price of gas — and the recent movement of that price — varies dramatically across key midterm states. In some states, like New Hampshire and Pennsylvania, prices have barely increased or even fallen over the last month.

Here's a look at the key midterm states where gas prices have spiked significantly in recent weeks, and what candidates are saying about the rising costs:

Arizona

In Arizona, a swing state host to highly contested races for governor and Senate, the price of a gallon of gas stands at $4.40 — a figure roughly 15% higher than the national average of $3.82, according to AAA. Moreover, the price of gas in Arizona has risen more than 8% over the past month.

Blake Masters, a Republican candidate for Senate, condemned the gas price spike on Wednesday in a tweet critical of his opponent, incumbent Democrat Mark Kelly, as well as Biden.

"Now in a desperate bid to try to save the midterms they're squandering our strategic reserve," Masters said. Biden retains sole authority over releases from the SPR, which currently stands at 57% capacity, according to the Energy Information Administration, or EIA.

Kelly, meanwhile, acknowledged the elevated prices last week, citing a general supply bottleneck. "From groceries to the gas we pump into our cars, it feels like everything is too expensive right now," he said. "I'm working in the Senate to fix our supply chains and bring down costs for Arizona's working families."

Wisconsin

In Wisconsin, where a high-stakes Senate race could determine which party holds the chamber, the price of a gallon of gas stands at $3.67, AAA data showed. While that price falls below the national average, it reflects a recent surge of more than 5% over the past month.

Republican incumbent Senator Ron Johnson, first elected in 2010, has attributed the high gas prices to spending increases and environmentally friendly initiatives supported by Democrats.

Earlier this month, Johnson said: "Make no mistake, this is the result of Democrats' reckless deficit spending and radical green energy policies."

To address the gas prices, Democratic candidate Mandela Barnes, the state's Lieutenant Governor, says on his campaign website he would end government subsidies for oil and gas companies, which he claims have enabled high profits.

Ohio

Another key battleground state is Ohio, where a close Senate race features author and venture capitalist J.D. Vance, a Republican, and Democratic Rep. Tim Ryan.

Gas prices in Ohio stand at $3.71, nearly 10 cents below the national average. AAA data showed. But the price has jumped about 7% over the last month.

In a debate between the two Senate candidates, on Monday, Vance faulted the Biden administration and Congressional Democrats for impeding investment in the U.S. energy sector that could increase oil output and bring down prices.

"That rising energy price that people see at the pump, that people see in your utility bills, that our farmers see when they're paying more for diesel," Vance said. "That was the direct result of policies enacted by Joe Biden and Nancy Pelosi and supported 100% by Tim Ryan."

Oil production in the U.S. last year was nearly identical to that seen over the final year of the Trump administration, in 2020, and greater than the amount produced in 2017 or 2018, according to data from the EIA.

Ryan, meanwhile, cited his vote for the Inflation Reduction Act, which is projected to cut the deficit over a 10-year period and slightly reduce inflation, according to the Wharton School of Business at Pennsylvania University.

To provide short term cost relief, Ryan called for a tax cut for working families that would ease the pain imposed by higher prices. "This is an opportunity for us to put more money in people's pockets," he said at the debate.

California

California, the state with the highest gas prices, could determine which party retains control of the House of Representatives. The state plays host to three toss-up House races, according to the Cook Political Report.

Gas prices in California stand at $5.83 per gallon, which puts the price about 52% higher than the national average, according to AAA data. That price has spiked nearly 8% over the past month.

In one of the toss-up House races, the Oakland-area 13th district, two challengers seek a seat left open by the retirement of longtime Democratic Representative Barbara Lee.

Adam Gray, a Democratic state assembly member running for the seat, faulted California's tax credit system, which he said in a debate last month offers a tax break for wealthy Tesla purchasers but leaves working-class people straining to afford high gas prices.

"We need to have a renewable energy policy that actually doesn't balance its book on the folks who can least afford to pay the bill," he said.

On the other hand, Republican candidate John Duarte, a farmer, blamed the high gas prices on environment-friendly Democratic policies that he says have limited oil supply.

"We need to develop domestic energy as a matter of opportunity and affordability for families," he said at the debate.