Nearly three-quarters of Coloradans surveyed in a recent poll said they had already been vaccinated or plan to do so.

The poll, conducted by Keating Research, OnSight Public Affairs and Melanson and released Monday morning, surveyed 528 Colorado voters between April 20 and April 26.

Sixty-three percent said they'd already been vaccinated and another 10% said they planned to be inoculated but hadn't done so yet. 

Twelve percent said they were unsure about getting vaccinated, and 15% reported they weren't going to receive a dose.

The poll also found that while 90% of self-reported Democrats said they'd already received or planned to get a dose, 56% of Republicans said the same.

Eighty-seven percent of respondents in the Denver and Boulder region of the state said they'd received or would receive a jab, compared to 64% in rural areas. 

The findings are more encouraging than a similar survey released by the state Department of Public Health and Environment in late March.

That effort reported that 62% of respondents had either received a dose or were planning to. Overall, 88% said they may receive a dose. 

But they come as policymakers in Colorado and across the country are considering how to better improve uptake.

The New York Times reported Monday morning that herd immunity through vaccination might be an unreachable target nationwide because of a combination of widespread hesitancy and the dominance of variants, which will require more people to be vaccinated to hit population-level protections. 

Last week, Colorado's state epidemiologist Rachel Herlihy told reporters that state officials believe the state will reach herd immunity in a matter of "weeks to month."

The herd immunity threshold is at least 70%, though Herhily said uptake might need to be higher because of the dominance of variant COVID strains.

Gov. Jared Polis also told reporters last week that "upwards of 80%" of eligible Coloradans were willing to be vaccinated.

He said many of the interested-but-not-yet-vaccinated were motivated either by hesitancy or laziness.

He touted the opening of all six of Colorado's mass vaccination sites to walk-in appointments as a further step to making doses more convenient for the general population.

The Colorado School of Public Health's Glen Mays told The Denver Gazette last week that the state had likely already vaccinated its highly motivated and most high-risk residents.

The remaining people -- who might be less at risk to severe disease than older residents -- will take time, he said.

As of Monday morning, more than 1.9 million Coloradans have been fully vaccinated and 2.6 million residents have received at least one dose.

The joint poll released Monday gave some insight into what's driving hesitancy.

Of the 12% who said they weren't sure if they'd get vaccinated, 63% said they were given pause because doses were developed too quickly and 52% had concerns about side effects.

There was also reported concern, though to lesser degrees, because of overall vaccine safety concerns and beliefs about the severity of COVID.

The Centers for Disease Control and Prevention, along with experts in Colorado and elsewhere, has said that though the Pfizer and Moderna vaccines were developed quickly, they were built on research and work that's unfolded for decades. 

Those two vaccines have reported flu-like side effects that subside after receiving the two doses.

The Johnson & Johnson vaccine, meanwhile, has had public issues, first with similar flu-like side effects that shut down one mass vaccination site in Colorado and then with a number of very rare blood clotting concerns.

But federal regulators and top health officials in Colorado, like chief medical officer Eric France, have said the flu-like symptoms experienced by Johnson & Johnson recipients were likely caused by anxiety and stress.

After determining the continued safety of the dose after the small amount of clotting episodes, federal officials have again given the Johnson & Johnson vaccine the all-clear.

As for Coloradans who reported being completely opposed, half said they thought COVID was overblown, followed by concerns about vaccine safety and the speed of these doses' development.