Coloradans will vote on an affordable housing measure for the first time ever this November, one that would divert nearly $300 million in annual funding toward a first-of-its-kind program.

Proposition 123 is unique in its breadth and scale, supporters and analysts said. It would support eviction defense, down-payment assistance, new housing development, the purchasing of land for future use and direct payments to renters. Its presence on an already crowded ballot comes as affordability anxiety among residents — and their elected leaders — continues to rise: A Colorado Health Foundation survey found that 86% of residents felt that housing is a very or extremely serious problem, second only to the cost of living.

If passed, Prop 123 could spur the construction of 10,000 affordable rental units each year, said Mike Johnston, the CEO of Gary Community Ventures, which is supporting the effort.

“We cannot afford a Colorado where Coloradans can’t afford to live,” Johnston told supporters at a kick-off event in Aurora last week. “And that is the moment we find ourselves in right now,  and the trajectory where we’re heading if we don’t make dramatic changes right now.”

If approved, Prop 123 wouldn’t raise taxes. It would instead allow the state to keep 0.1% of taxable income each year, projected at $290 million from 2023 onward, as a carve-out of the Taxpayer’s Bill of Rights, or TABOR.

It’s not a silver bullet, supporters and opponents both say, and an argument against the measure listed in the state’s ballot guide contends it won’t solve the “underlying causes of high housing costs.”

But it’s a “first step in the right direction, as we have been remiss for far too long,” said Denise Maes, the deputy executive director of the Village Exchange Center, which hosted the campaign’s launch event last week.

That first step may also mean that TABOR checks could be lower going forward, a fact that’s drawn the criticism of the conservative group Advance Colorado. Senior advisor Michael Fieldssaid Coloradans need their full tax refunds now more than ever. He also questioned whether the measure would actually build as many units as advertised.

According to an analysis conducted by the Colorado Legislative Council, Prop 123’s passage could mean TABOR checks would be $43 lower in 2023 and $86 lower in 2024.

Johnston said lower refund checks were the “worst-case scenario”; the best-case scenario, he said, is that Prop 123’s annual cost would be absorbed, without impact to the taxpayer, thanks to other budgetary concerns being phased out this year.

Still, the outsized focus on TABOR refunds this year may present a challenge to anything that may affect them in the future. But Johnston said the creation of a reliable funding stream without raising taxes is a sell to voters. The measure, which was placed on the ballot via voter petition, has already gained support: Johnston referenced a recent Colorado poll conducted by the American Civil Liberties Union, which found 77% of residents support the affordable housing measure. It’s also already received scores of endorsements from politicians and organizations, including the Colorado Association of Realtors, the nurses and hospital associations, and various housing nonprofits.

The money diverted by the measure would go toward several programs, including “land banking,” which would give forgivable loans and grants to local governments and nonprofit organizations to buy land for future housing development.

Another pile — as much as $61 million — would be put toward financing new affordable units, and up to $58 million more would go to help first-time homebuyers with their down payments. Tens of millions would be set aside to directly combat homelessness — for housing vouchers, eviction defense and rental assistance, among other things.

The largest projected share — somewhere between $69.6 million and $121.8 million annually — would be steered toward the measure’s most innovative approach: replacing investment banks with the Colorado Housing and Finance Authority, and giving the proceeds of the investment to the renters themselves.

Normally, housing developers get most of their funding from a standard bank with relatively low-interest rates, Johnston said. They get the rest from investment firms that expect substantial, and speedy, returns.

Under Prop 123’s model, the CHFA would loan the money to approved developers and expect significantly smaller returns — 2%, Johnston said, rather than 20%. That allows rent to be lower, but it also means that money made from the properties would be given back to renters in a savings account. Anyone who’s lived in the affordable units for at least a year would qualify, according to the measure, and the money would be theirs to use.

Peter LiFari, the executive director of Maiker Housing Partners, called the equity-sharing provision “unique and inspirational” in an analysis for the Common Sense Institute, a free enterprise-focused think-tank. He said in a subsequent interview that it’d be the largest and most ambitious such program in the country, a “transformative” way for renters to build equity.

There are risks, LiFari said: Local governments must opt-in to Prop 123, and they’d have to meet certain benchmarks. Participating municipalities and counties would have to increase their affordable housing stock by 3% per year over three-year cycles — so if a county has 100 affordable units in 2023, they’d have to hit 109 by 2026, Johnston said. The measure also requires that local governments approve new affordable housing development within 90 days, in an attempt to expedite lengthy, and costly, approval delays. The measure would set aside several million dollars so local agencies could hire more staff to meet those goals.

The local buy-in is key, LiFari, who runs an Adams County housing authority and has served on state and national boards addressing the issue, said in an interview. The measure would give as much as $5.8 million to help local authorities staff up and meet the requirements and Johnston said he believes there will be “heavy” — and immediate — buy-in from local authorities should Prop 123 pass.

Still, LiFari said the expedited approval process runs counter to how local authorities have operated for decades.

“We don’t build housing in Colorado, we don’t like approving housing, and this whole measure is asking local governments to do the exact opposite of what most of them have been doing for the last 20 to 30 years,” he said.

If counties or cities balk at meeting the 3% goal or 90-day turnaround timeline, they could decide to avoid the program altogether. Unused money would sit in an account, slowly piling up and drawing the attention of legislators in search of money for other projects, LiFari said.

Voters supporting it is only the first hurdle, he said. Local leaders will have to back it, too.

“If local governments belly up to the bar and continue to come back,” he said, “it can do tremendous good.”