A deal to avert a ballot box battle over property taxes cleared the halfway point of the legislative process Wednesday, setting it up for final passage later this week.

Just after noon, the Colorado House passed the measure, which would provide homeowners and other property owners with modest additional tax relief, on a 45-18 vote, as 15 of the majority Democrats voted against it. By mid-afternoon, the bill cleared its first hurdle in the Senate with a unanimous vote out of committee, and it passed a first Senate voice vote shortly before 6:45 p.m.

That sets the bill up for final passage — and a trip to Gov. Jared Polis’ desk — Thursday.

House Bill 1001builds off a property tax cut signed into law in May. If passed, it would reduce property tax collections statewide by about $254 million — on top of the $1.3 billion cut passed in the spring — by further trimming the state’s assessment rate. That rate, along with local mill levies, is used to establish how much in taxes the property owner owes.

RELATED: A quick guide to the special session on property taxes.

The change would save the average homeowner about $62 for the upcoming property tax year and $179 the following year, according to an analysis by the Colorado Fiscal Institute; lawmakers’ estimates for the initial impact have been slightly higher. The bill also would expand the nonresidential properties that qualify for commercial rates set in the spring measure, passed as Senate Bill 233.

The progressive think tank’s analysis found that 62% of the tax cuts proposed in the special session bill would go to nonresidential property owners. The analysis did not have an average estimated savings for that class of property.

But the true stakes of the special session, backers of the deal say, is that it will result in Advance Colorado, a conservative advocacy group, yanking initiatives 50 and 108 from the November ballot. If passed by voters, those measures would force deeper cuts to the assessment rates, worth potentially billions of dollars, and set stricter caps on how much property tax revenue local governments can keep.

“For the yeses and the noes, I believe that passing this bill and getting those initiatives off the ballot is the responsible, most important thing that we can do today — that we can do for the future of this state,” House Speaker Julie McCluskie told her colleagues shortly before the vote.

The House also passed a proposed ballot measure Wednesday that would have required local voters to approve of any future property tax changes instituted by a statewide vote. Democrats had embraced that bill as a way to help prevent new statewide property tax wars — like the one that sparked the special session.

But Republicans opposed it, and that opposition ultimately sank the measure later in the day in the Senate, where at least one Republican needed to back the bill. Sen. Chris Hansen, a Denver Democrat who sponsored the measure, voluntarily pulled the bill during a committee meeting.

That leaves lawmakers with a written promise from Advance Colorado and its allies, including the business-oriented Colorado Concern, not to pursue similar property tax measures for at least six years should the property tax bill pass as written.

Some lawmakers had bristled at being pulled into a special session to codify a deal already agreed to by the governor, legislative leaders and outside groups. That frustration prompted a series of speeches from House Democrats decrying the process and lamenting that they were being forced to pick between cutting local services now or risking deeper cuts if the ballot measures pass.

“I don’t work for somebody who is not on this floor. Or even, dare I say, behind the glass,” said Rep. Jennifer Bacon, a Denver Democrat and the House’s assistant majority leader. She was referring to the governor’s office, located a floor below, and to lobbyists who watch the House work through glass windows.

She emphasized: “It is our job to make law.”

As Bacon spoke, a large number of lawmakers from both parties stood at their desks, a sign of solidarity in the chamber.

Rep. Stephanie Luck, a Penrose Republican, criticized the process that sparked the special session. Rep. Tim Hernández, a Denver Democrat who lost his primary in June, spoke at length about his own upbringing — and the property his family wasn’t ever able to afford — and contrasted it with the forces that he said compelled lawmakers back to the Capitol this week.

“There are a lot of brilliant poor kids who grow up in this state, whose families don’t get the opportunity to own property, who don’t get the opportunity to come here and be heard in this legislature — poor folks, oppressed folks who don’t get a special session,” Hernández said.

After lengthy testimony from Democrats and Republicans alike, McCluskie and Minority Leader Rose Pugliese — a Republican who co-sponsored the bill with the speaker — both acknowledged concerns from within their own causes.

But they asked their members to support the deal anyway.

“Is it a move to play defense right now? You bet it is. We provide assurances to our communities. We provide assurances to our hardworking families that we’re not going to take $630 million from our schools,” McCluskie said, referring to one projected impact of Initiative 108’s passage.

The bill passed the House comfortably, though with progressive Democrats casting the majority of the no votes.

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