State services — including schools — are effectively paying to maintain Utah’s roads, to the tune of about $600 million a year, according to Senate President Wayne Niederhauser.

Utah’s elected leaders, most of them conservative Republicans, always are reluctant to increase taxes — particularly in an election year.

But they may worry too much. A plurality of voters would approve of paying more per gallon of gas to support Utah’s road network, according to a new poll by The Salt Lake Tribune and the University of Utah’s Hinckley Institute of Politics.

The poll found just under 50 percent of registered voters support a higher gas tax. Nearly 14 percent said they strongly support and 36 percent somewhat support the idea.

Could the state raise enough money from drivers through gas taxes to free up $600 million for spending on other issues like education and health care?

“Politically, no,” Niederhauser, a Sandy Republican, told reporters this week.

“Not even toll roads,” added Sen. Stuart Adams, R-Layton. The Legislature will be considering expanding tolling in the state, including on people who drive up Little Cottonwood Canyon, under a rare bill sponsored by the Senate president.

Gas taxes have been a primary way states and the federal government pay for roads and highways, but they also have become a less reliable revenue stream as cars become more fuel-efficient.

Some say the tax has outlived its purpose as more drivers buy electric and natural gas vehicles, and avoid paying gas taxes altogether.

“Within the next 10 years, you’re going to have 10-20 percent of your vehicles on the road that are nongas,” Niederhauser said. “At that point, the gas tax, we have to look deeply and say this is maybe an obsolete tax.”

Still, the Legislature has its eye on collecting money in any possible way from drivers to pay for roads as legislative leaders point to highway spending as a reason it’s difficult to spend as much on public education as some advocates want.

They’re considering raising the gas tax and other driving-related fees. There’s also interest in rolling out a pilot program in which drivers pay for the miles they travel, which would ensure owners of the most fuel-efficient vehicles don’t escape paying their share of road funding

Republicans are less likely than Democrats and unaffiliated voters to support raising the gas tax, the poll found. Fifty-three percent of registered Republicans oppose a gas-tax increase to improve roads and 45 percent support a hike. Meanwhile, 67 percent of Democrats and 49 percent of independent voters said they’d support raising their taxes.

The state’s gas tax is 29.4 cents per gallon of gasoline and diesel. The federal government adds another 18.4 cents per gallon of gasoline, and 24.4 cents for diesel.