WASHINGTON (AP) – The Senate is poised Tuesday to pass an overhaul of highway and transit programs that gives states greater flexibility over how they spend federal aid and streamlines environmental regulations to get projects built faster.

About 20 amendments are set to be decided in an all-day marathon of voting. They include proposals to allow states to charge tolls on interstate highways, provide tax credits for alternative energy and cars that run on natural gas, and permit more flights over the Grand Canyon and other national parks.

The measure would spend $109 billion over less than two years. Democrats say the bill would create nearly 3 million jobs, but economists are skeptical of those claims.

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