With wolf pack supporters planning on Tuesday to submit more than 208,000 signatures supporting a November 2020 ballot measure calling for the reintroduction of wolves to Colorado, voters could soon hear a pitched howling over wolves for most of next year.

“This is our last opportunity to do it right and to restore the balance,” said Rob Edward, whose  Rocky Mountain Wolf Action Fund has been collecting signatures since June for a 2020 ballot measure — now called Initiative 107 — that directs the Colorado Parks and Wildlife Commission to craft a plan to restore and manage gray wolves in Colorado by the end of 2023.

The group needs about 124,000 valid signatures to qualify for the 2020 ballot. Their deadline to collect them is Friday.

As the group transitions from harvesting signatures to swaying voters, opponents of wolf reintroduction are girding for battle. And it’s a new type of fight for opponents of wolf reintroduction, who in other states across the West and Great Lakes region have lobbied wildlife commissioners — not voters — to oppose reintroduction. The Colorado Stop the Wolf Coalition is strategizing a first-ever public campaign, seeking to educate voters on potential negative impacts of introducing the wolf to the state.

“There are a lot of people who don’t want wolves brought into Colorado. We just can’t sustain another predator in this state,” said Denny Behrens, co-chair of the Stop the Wolf Coalition.

The coalition has gathered resolutions from 10 counties opposing reintroduction of wolves in the state. It has found high-profile supporters like Greg Walcher, the former head of the Colorado Department of Natural Resources.

In a statement announcing his support for the coalition and its fight against Initiative 107, Walcher said seeded wolves in Colorado could “decimate other important wildlife, and their impact on rural areas could be devastating.”

MORE: Could Colorado see the return of grizzlies, wolves and wild bison? Here’s how Montanans coexist with them.

Colorado is the last battleground for restoring wolf populations after more than 40 years of federal and state efforts to introduce wolves in the Southwest, Northern Rockies and Great Lakes regions.

In Montana, Wyoming, Idaho, New Mexico, Arizona and around the Great Lakes, wolf reintroduction was directed by wildlife officials following the federal Endangered Species Act that has protected gray wolves since 1983. A ballot measure in Colorado — the missing link connecting wolf populations between Mexico and Canada — would mark the first time that voters, not federal laws, directed state wildlife officials to restore wolves.

“Conservationists and biologists have been working with the Fish and Wildlife Service and different agencies for years, trying to convince them to do this in Colorado, and we keep running up against a brick wall,” said Edward of the direct-to-voters appeal for wolves.

There are about 5,500 wolves spread across nine U.S. states right now, according to the U.S. Fish and Wildlife Service. The Department of the Interior in March proposed removing the gray wolf from protection, citing its growing population.

The proposal has drawn the ire of wolf advocates who fear delisting could lead to more wolf hunting and trapping in some areas. Advocates submitted more than a million comments opposing the suggested removal of endangered species protection for wolves.

Wolves last roamed Colorado in the 1940s, but they have wandered into Colorado from neighboring states, even as recently as last July.

Opponents don’t care about wandering wolves. They do not like the wolf advocates’ plan to introduce at least 20 to 30 predators to Colorado, which could grow to a population of 250 or more wolves over the course of a decade. Behrens said the idea that wolves would remain on the West Slope “is pretty absurd.”

“They will travel great distances. You will have wolves in Woodland Park and Estes Park. You are going to have wolves all over the place in a matter of years,” he said. “Why would you take a wolf from Canada where it roams free and bring it down to Colorado and turn it loose with almost 6 million people and think there’s not going to be any conflict? There will be conflict from day one, and it’s not fair to the wolf to do that.”

Edward, with the wolf fund, points to growing wolf populations in places like Yellowstone National Park, where millions of annual visitors have not had conflicts with wolves since reintroduction there in the 1990s.

“This is just not an issue. Western Colorado is 70% public land, so it’s not going to be developed and full of people,” Edward said.

Opponents of the wolf reintroduction plan say the flow of out-of-state money into the wolf reintroduction effort shows “this is not a Colorado campaign,” Behrens said.

California’s Tides Center — which supports progressive causes — has given the wolf campaign about $264,000. The Colorado Sierra Club gave more than $10,000, according to reports the campaign filed with the Colorado Secretary of State. Between July and October this year the Rocky Mountain Wolf Action Fund reported $625,000 in contributions and about $653,000 in expenses, most of that going toward Landslide Political, a Utah-based signature gathering firm.

“Less than 1% of the money they’ve raised has come from Coloradans. That’s pretty telling,” Behrens said.

Edward said since most of western Colorado is federal land, it’s not surprising that people from all over the country support efforts to restore wolf populations on public lands.

“It is perfectly appropriate for people from across the country to donate to this campaign,” said Edward, who served on a wolf advisory group in 2005 that ultimately recommended that the state’s wildlife commission oppose reintroducing wolves.

Colorado Parks and Wildlife has not voiced support or opposition to the ballot proposal, but in 2016 the Colorado Parks and Wildlife Commission adopted a resolution affirming the wolf advisory group’s recommendation opposing the intentional release of any wolves in Colorado.

A legislative analysis of Initiative 107 shows the state would spend about $811,000 in the first two years of the reintroduction effort.

A fiscal note from Colorado Parks and Wildlife — obtained via an open records request by the Stop the Wolf Coalition — shows that after planning costs,  implementation of the wolf reintroduction plan would cost $4.1 million, including new wildlife biologists and payments to ranchers who lose livestock to wolves. The cost for the first eight years of the reintroduction effort, which CPW estimated would involve 45 released wolves over a five-year span, would be $5.7 million.

With what could be the country’s final battle over wolves now shifting toward Colorado voters, both sides say they have the support to win.

“As far back as 1993 and 1994, we have polling showing that people on the Western Slope support recovery by a majority margin,” Edward said.

Once “a full-blown education campaign” reaches voters, Behrens said, “we will see a huge input of funding from Coloradans who don’t want this.”