President Biden touted the effectiveness of workplace vaccine mandates and urged companies to begin instituting them on their own during a visit to the Chicago area Thursday as his administration rushed to create a federal rule that will require companies with more than 100 employees to institute vaccination or testing protocols among their staffs.

Biden initially shied away from calling for coronavirus vaccine mandates but has fully embraced them with the coronavirus reignited in the country in recent months, hampering the economic rebound and his efforts to move past the pandemic.

Since Biden began his for push for more workplace vaccine mandates, evidence that they effectively boost vaccination rates has piled up.

Biden met with the chief executive of United Airlines, the first airline to institute a vaccine mandate for employees, and visited the worksite run by a construction company, Clayco, that recently announced a vaccine or testing requirement for its workers.

Many private companies and some states have issued vaccine mandates for health-care workers in recent weeks, and the White House came armed with statistics showing that mandates are working at increasing vaccine saturation among target populations, despite a small but vocal amount of resistance among anti-vaccine factions on the right.

“With vaccinations, we’re going to beat this pandemic finally,” Biden told a group of unionized workers in yellow vests and hard hats at the Clayco project, a development for Microsoft in Elk Grove Village, Ill. “Without them we face endless months of chaos in our hospitals, damage to our economy and anxiety in our schools. Empty restaurants. Much less commerce.”

He called the vaccine requirements “tough medicine” that he came around to only after seeing how many people refused to get vaccinated, amid rising caseloads across the country from the delta variant.

Biden advisers have long seen his handling of the pandemic and the economy as the chief driver of how Americans think about him.

The resurgence of the virus, driven by the delta variant and the refusal of millions of people to get vaccinated, has coincided with a dip in Biden’s approval ratings in recent weeks. Immigration issues and the chaotic withdrawal from Afghanistan have also factored into that slide.

But the White House’s support for vaccine mandates in the past month has proved popular, giving the president some hope of regaining approval from the public, Biden allies say.

Federal workers and contractors are now facing strict vaccine requirements on direction from the White House, and once the Labor Department is finished with its emergency rule, similar provisions will extend to an additional 80 million Americans or more, with the additional option of testing.

Air Force One touched down Thursday afternoon in Chicago, where Biden was greeted by Illinois Gov. J.B. Pritzker (D), Democratic Illinois congressmen Mike Quigley and Raja Krishnamoorthi and Chicago Mayor Lori Lightfoot (D), with whom he had a brief conversation on the runway.

Biden was then off to the site being run by Clayco, whose CEO, Bob Clark, gave tens of thousands of dollars to Biden’s presidential campaign efforts. The company is supportive of the vaccination and testing requirements.

Vaccine mandates appear to be effective at increasing vaccination rates among the populations they are designed for.

More than 99 percent of employees at United Airlines got vaccinated, in addition to some 2,000 who have applied for religious or medical exemptions. Workers whose religious exemptions are approved will be put on unpaid leave, the company said; medical exemptions will be put on medical leave.

In New York state, which instituted one of the country’s strictest vaccine mandates for health-care workers, employee vaccination rates rose from the 70 to 80 percent range when the proposal was announced in August to more than 95 percent at many hospitals by the deadline last week. Hospitals in California reported similar results.

In Illinois, Biden noted that 97 percent of active-duty service members are now vaccinated after the Defense Department issued a requirement, up from 67 percent six weeks ago.

“That’s how quickly it moved,” he said. Overall, the country has reduced the total numbers of unvaccinated people by about a third since July, to around 67 million, Biden said.

During the tour at the Clayco site, Biden greeted workers with arm bumps and asked questions about their work. “Tell me what you’re doing here,” he said, asking “How much will this be built out?” and “It is union?” He was told the facility will be completed early next year.

The visit came as Labor Department officials work quickly to draft and implement an emergency rule, on orders from the White House, that will require all private companies of at least 100 employees to require vaccinations or regular testing. The requirement is expected within weeks, although the administration has not given a specific date for its release.

The rule is popular with the general population, with some 58 percent of the public in support, according to a recent Gallup poll. Some 60 percent of people support vaccine requirements for all federal employees and 63 percent support requiring hospitals that receive federal reimbursements to institute vaccine mandates for their staffs.

Many players in the business community say they are willing to work with the Labor Department on the effort as well, in contrast with the typical business response to new workplace regulations, as the delta variant has exposed how vulnerable the economy remains to the spread of the virus.

But the requirement is attracting fierce opposition from Republican state officials as misinformation about vaccines proliferates online, helping to create a robust base of anti-vaccine sentiment on the right.

On the way to the events Thursday in Illinois, Biden’s motorcade passed by a sizable protest with lots of pro-Donald Trump and anti-Biden signs. One sign said “Mandates are 4 Greed and power.”

Two dozen state attorneys general sent the White House a letter in September threatening legal action over the requirement, although many experts say that the requirement is well within the Labor Department’s legal bounds.

Biden’s calls for mandates also appear to be earning back some support from the public at large. In the Virginia governor’s race, the year’s marquee election, Democrat Terry McAuliffe is touting mandates and Republican nominee Glenn Youngkin’s opposition to them.

Sullivan reported from Elk Grove Village.