President Donald Trump, according to Sen. Tom Carper, D-Delaware, has voiced support for a one-time 25-cent increase in the federal fuel tax, which stands to hit families in Mississippi and Wyoming harder than others.

The proposal to raise the gasoline tax by 25 cents would increase it to 43.4 cents per gallon. Such a hike would add $394 billion in revenue over 10 years, according to the U.S. Chamber of Commerce.

The resulting financial impact would not be felt “uniformly” for individuals and families across the nation, according to a new analysis from Freedom Partners. Excluding commercial or industrial expenses, annual fuel tax consumption costs for households in Mississippi would rise to $390.62, the highest, according to the nonprofit group. Wyoming would face the second-largest cumulative fees, at $380.29 per household. Meanwhile, South Carolinians would pay $377.49.

Drivers in California, Texas, Florida, Pennsylvania and New York would pay the most in gasoline taxes, with the total state and federal tax liability in the Golden State surging to about $14.2 billion. In Texas, the amount would be more than $8.7 billion, while Floridians would face $7.2 billion.

The states that would experience the largest percentage increase in gas tax costs over 2016 rates include Alaska, Oklahoma, Missouri, Mississippi and New Mexico, with Alaska potentially seeing an 81% increase in consumption costs, which would amount to $281.77 per household. For Oklahoma, the percentage increase amounts to 71%, or $324.14 per household.

Discussions to raise the gas tax come as the White House recently detailed its plan to overhaul the nation’s infrastructure. The initiative calls for $1.5 trillion in spending over the course of a decade and relies heavily on states to attract outside private investment to fund major projects. Shifting the funding burden more heavily onto states rather than providing federal dollars for infrastructure projects could allow for more flexibility to develop projects catering to specific local needs.

The gas tax has not been raised since 1993 and is currently set at rate of 18.4 cents per gallon. It has not kept pace with inflation.

The White House has not confirmed that Trump supports a one-time, 25-cent increase in the federal fuel tax, but has said that it is considering all options.