MINNEAPOLIS (WCCO) — On Wednesday, the Republican-led Minnesota Senate rejected a plan from DFL Gov. Tim Walz to raise the state’s gasoline tax by 20 cents.

Part of the opposition among drivers comes from deep skepticism about where the gas tax money really goes.

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The current 28.6 cent tax on every gallon raises $925.7 million a year — but it’s not enough to sustain Minnesota’s vast transportation system.

So where does that money go?

It’s not that complicated — despite a flow chart from the Minnesota Department of Transportation that looks like a chalkboard scene from the movie “A Beautiful Mind.”

Here’s what’s important:

The state Constitution says the gas tax can only go to roads and bridges.

Here’s the language from the Minnesota Constitution:

“The legislature may levy an excise tax on any means or substance used for propelling vehicles on the public highways of this state or on the business of selling it. The proceeds of the tax shall be paid into the highway user tax distribution fund.”

One-hundred percent of the Motor Vehicle Fuel Tax money goes into the Highway User Tax Distribution Fund. The state divides the money between highways, county roads, city streets and local bridges.

The gas tax money does not pay for light rail transit or for buses. That’s a separate sales tax in the metro area.

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And money from counties and the federal government. That doesn’t make it any less controversial.

Minnesota’s 28-cent gas tax is the 24th highest in the nation. Raising it by 20 cents — to 48 cents a gallon — could make Minnesota one of the highest in the nation.

MnDOT says it’s about $600 million short each year for needed road construction — and that’s just for state highway work.

A recent infrastructure report card gave Minnesota’s roads a D+.

Here Are Sources We Used For This Reality Check:

MN Law Regarding Fuel Tax

MN House Research: Transportation Funding Overview

Senate Transportation Committee Breakdown of Transportation Funding

MnDOT Funding Breakdown.

US Energy Information Administration: Nationwide Gas Tax

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MN House Research Highway Finance Executive Summary