In a departure from last year's big transportation bills, state legislatures this session have mostly shied away from increases in funding -- and the higher taxes and fees that come along with them.

Lawmakers in Rhode Island and New Hampshire approved small hikes in their state fuel taxes, and Missouri legislators asked voters to decide in August whether to hike the state's sales tax for transportation projects. But largely, with elections around the corner, most states played it safe. "States are deciding what's politically feasible this year, and what's not going to upset the apple cart too much in an election year," said Sean Slone, a transportation expert with the Council of State Governments.

The limited action this year comes after a burst of activity last year. Legislators in Pennsylvania and Virginia reached breakthroughs after years of failed attempts to shore up infrastructure funding. Maryland, Massachusetts, Ohio, Vermont and Wyoming also passed significant transportation funding measures.

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Uncertain federal funding is straining states' transportation budgets. Federal reimbursements to states could start to slow in as little as a month as the account that pays for the bulk of federal highway spending is drawn down. "States have been seeing the writing on the wall for quite a while now that maybe the federal government isn't going to be most reliable partner for the foreseeable future. So they're trying to explore their options," Slone said.

New Hampshire legislators, who voted down a gas tax hike last year, agreed this year to raise fuel taxes for the first time since 1991. The state's per-gallon tax will increase by 4.2 cents starting in July, on top of the current 18-cent rate.

The measure was sold as a way to make up for the gas tax's lost buying power, as gas became more expensive but the rate remained the same. The amount of the tax hike was determined by adjusting for inflation over the last decade. But the law won't adjust for inflation in the future. In fact, the gas tax hike will expire once bonds supported by the new revenue -- which will pay for widening of Interstate 93 -- are retired.

The new money will also be spent on resurfacing projects and shared with municipalities to fix bridges. The law also requires the state to stop collecting tolls on a single turnpike interchange in southern New Hampshire.

Getting rid of tolls was the catalyst for Rhode Island's decision to increase gas tax. Legislators there eliminated a 10-cent toll for the Sakonnet River Bridge that brought howls from local residents. Instead, lawmakers bumped up the state's gas tax by 1 cent a gallon and increased vehicle inspection fees. The law also ties the gas tax rate to inflation in the future.

Missouri's plan to increase its sales tax by 0.75 percentage points for a decade will be in the hands of the voters in August. The proposal would generate $480 million a year for the state, plus another $54 million for counties and municipalities. The Missouri Department of Transportation named 800 projects it could fund with the additional money, including badly needed repairs on Interstate 70 between Kansas City and St. Louis.

But the measure must clear significant hurdles to make it into law. The first is a lawsuit challenging the description of the measure on the ballot. The second, and more formidable, is timing. Gov. Jay Nixon, a Democrat who opposes the Republican-authored plan, placed the proposal before voters in the August primary, rather than in the November general election. That gives backers of the plan less time to convince voters to approve it. It also means that a smaller, more ideologically driven electorate will decide the fate of the sales tax hike.

Governors in Delaware, Michigan and Washington state tried to increase transportation funding, but failed.

Michigan lawmakers couldn't strike a deal on raising the state gas tax or finding other sources of new road money. In a string of votes that reached late into the night, the state Senate rejected proposals to hike the gas tax by 25 cents a gallon over five years; raise the wholesale gas tax; and ask voters to approve a sales tax hike to boost transportation money.

But Michigan legislators did sign off on short-term relief to help the state transportation department and localities absorb the costs of plowing, salting and patching roads damaged in last winter's harsh weather.

The Oregon Department of Transportation shut down its efforts to build a bridge over the Columbia River for Interstate 5 and a light rail line, because Washington state legislators failed to find money to pay for the northern state's share of the project.

Washington Gov. Jay Inslee, a Democrat, has pushed for additional transportation money, which would include the Columbia River Crossing among other projects, since he took office two years ago. The proposals languished in the state Senate, which is controlled by a coalition of Republicans and renegade Democrats.

Delaware Gov. Jack Markell failed to get a gas tax hike through his state's legislature, even though the chambers there are controlled by fellow Democrats. Markell wanted to increase Delaware's gas tax by 10 cents a gallon, but the proposal went nowhere. After the proposal stalled, Markell's administration announced it would hike weekend tolls along Route 1 to pay for road maintenance and repairs.