Residents in Holladay rejected a controversial high-density development on the site of the old Cottonwood Mall, according to unofficial election results.

In a ballot measure that went before voters while still under challenge in the Utah Supreme Court, those early results, which included the bulk of mail-in ballots, went heavily against Proposition 14, 57 percent to 43 percent.

The vote reverses the Holladay City Council’s approval of the 57-acre residential and commercial development, essentially restarting the city’s lengthy planning process.

That is the result sought by Unite for Holladay, a group of residents opposed to the development, which has been dubbed Holladay Quarter. The group has conducted a robust campaign in recent weeks including mailers, yard signs and automated calls — while supporters of Proposition 14 stayed largely silent.

“We’re thrilled,” said lead organizer Brett Stohlton. “This sends a clear message that Holladay deserves better and it really is a referendum on elected officials finding a better project for the old mall site.”

For city officials and the developers, Tuesday’s vote was not supposed to have taken place. They challenged the measure before the Supreme Court in mid-September and, based on hints from the justices, had expected a ruling nullifying the vote well before Election Day.

But more than six weeks after hearing hastily convened oral arguments, the state’s high court still hasn’t ruled.

Holladay Mayor Rob Dahle predicted last week Proposition 14 would likely go down to defeat as a result, given that supporters of the project and developers had not campaigned in its favor while in that legal limbo.

“I’m not shocked,” Dahle said when the final result was in. “Everybody assumed the court would have weighed in at this point.”

The mayor said the issue had been divisive and that he now hoped Holladay could move forward with other pressing community issues.

For nearly two years, Utah developers Ivory Homes and Woodbury Corp. have been pushing to bring a massive housing, office tower and retail development to the former mall site near 4800 S. Highland Drive — including a 775-unit high-rise apartment complex and 210 single-family homes.

A spokesman for Ivory Homes declined to comment Tuesday evening, but said company officials would be meeting with partners on the project on Wednesday to chart its future.

In an interview last week, Ivory Homes CEO Clark Ivory called the vote “zoning by referendum” and warned the project could fall apart with further delay and a public vote in opposition — regardless of how the Supreme Court might rule.

The city held more than 20 public hearings reviewing and updating details of the massive mixed-use project. That culminated in May with city approval of a final site development plan and a contract with developers that detailed how the mall site would be built out.

Though the project is said to be worth nearly $560 million to Holladay and would contribute significantly to the 19-year-old city’s tax base, it also involves high-density housing and a series of multistory residential and office towers that have drawn concern from some residents.

Opponents with Unite for Holladay contend that Holladay Quarter is too big and too dense, threatening to snarl traffic and alter the quality of life in the suburban city on Salt Lake County’s eastern bench.

Opponents of the development filed petitions over the summer with City Clerk Stephanie Carlson seeking a public vote on the two key City Council decisions giving the project a go-ahead, the contract and the master plan.

City officials rejected the petitions, saying approval for Holladay Quarter was “administrative” and simply applied existing zoning rules, making it ineligible for a citizens referendum. But, recognizing the issue fell into a legal gray area, the city also granted Unite for Holladay a spot on the ballot while all parties took the issue to court.

Third District Judge Richard McKelvie ruled quickly that the City Council’s approval of its contract with Ivory Homes was administrative.

But the site development master plan, McKelvie said, was instead a “legislative” act, meaning that it made new, wider policy instead of simply applying existing law and could be subject to a public vote.

Both sides took the matter to the Utah Supreme Court, where the case sat undecided as of Monday.