The Colorado Senate approved legislation Monday to ask voters in November to give up part of their future tax returns to help fund education and transportation.

Two bills – one to put the question on the ballot and the other to authorize spending it – passed 21-14.

The legislation doesn’t need the governor’s signature, since the legislature is authorized to refer matters to the ballot.

In some years, when the state brings in more revenue than a constitutional spending cap allows, the excess money is returned to taxpayers.

Voters this year will decide whether to forego those returns. One-third of the money would go to K-12 education; one third to higher education; and one-third to transportation.

If the law applied this year, the excess would be about $65 million. In future years, as the economy cools, it might not be anything.

Senate Republicans fought the effort Monday, saying it was unnecessary and takes money away from future taxpayers without giving them any say in it.

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TABOR, passed by voters in 1992, is a crown jewel to state Republicans, who say it controls spending and the size of government.

Voters also get to approve any new taxes and most major spending decisions, a constitutional caveat unaffected by the November election.

The outcome of November’s ballot question also doesn’t necessarily bind future legislators from spending the TABOR money on other priorities.

Senate Minority Leader Chris Holbert, a Republican from Parker, said voters have been promised money for transportation in the past, only to see road-and-bridge money fall farther and farther behind population growth.

“To the taxpayers of Colorado, don’t fall for it again,” he said on the Senate floor. “The secret to funding transportation is to use the funds that we already have.” 

Democrats have tried for years to chip away at TABOR, which they say prevents the state from investing in vital programs related to the state’s growth and prosperity.

Republican groups on Monday were quick to bemoan the fact that TABOR is going before voters.

Jesse Mallory, the state director for the Colorado office of the conservative group Americans for Prosperity, said the vote Monday “merely confirms what we already know about legislators in Denver and their fiscal restraint: They have none.”

He called TABOR “the only safeguard against an over-reaching government.”

Michael Fields, executive director of the conservative advocacy group Colorado Rising Action, said in a statement: “The bill sponsors have said that keeping our tax refunds isn’t a real funding solution for education and transportation, so this is clearly more about chipping away at the Taxpayer’s Bill of Rights. We anticipate that voters will reject this tax increase on the ballot in November as we have the last several statewide tax increases.”