FOR MOST of the past six years, Republican Gov. Charlie Baker has been ranked as the most popular governor – or close to it – in America. One Boston Globe headline referred to him as “Teflon Charlie,” and CNN’s Chris Cillizza marveled at Baker’s strong poll numbers – among Democrats.

Could the COVID-19 vaccine rollout end Baker’s popularity?

Criticism of Baker mounted as national metrics showed Massachusetts lagging in vaccine distribution, but then the numbers began to turn more positive earlier this week. All that positive momentum was wiped out on Thursday when the state’s website for making vaccination appointments crashed and sputtered all day long. Baker acknowledged that the crash was “awful” and said he “is pissed off.” But for many, it was the last straw.

The Globe reported how unusual it was that Baker was facing backlash from all corners of government. A February 16 letter to Baker from the state’s entire congressional delegation minus US Rep. Richard Neal, who wrote his own letter, expressed “serious concerns” about vaccine distribution and urged Baker to create a centralized pre-registration system to help people make vaccine appointments.

Hospitals have expressed frustration that Baker diverted vaccine doses away from them and to mass vaccination sites, a step Baker said he took to ensure speedier distribution.

Attorney General Maura Healey, a Democrat, said that decision will increase racial disparities. She wrote on Twitter that hospitals have been actively reaching out to communities of color. “Turning off the supply to our hospitals isn’t fair to the people disproportionately hurt by COVID, stuck at home, without computers, or someone to navigate websites or a ride to Foxborough,” Healey wrote.

Baker also took criticism for taking doses from municipal vaccine sites to send them to regional collaboratives and mass vaccination sites. Attleboro Mayor Paul Heroux called that decision “an absolute disaster,” a sentiment echoed by other municipal leaders, including Somerville Mayor Joe Curtatone.

The Democratic-led Legislature – which has worked closely with Baker for years – took the unusual step of announcing that it will hold an oversight hearing related to vaccine distribution.

Even before Thursday, people were poking fun at the fact that a software engineer on maternity leave built a more user-friendly vaccine appointment website than the Baker administration –  after which the administration improved its site.

On Thursday, after 1 million more people became eligible for vaccines and the state’s website crashed, Democratic Senate President Karen Spilka and House Speaker Ron Mariano said they were “disappointed.” Democratic US Sen. Ed Markey called it “unacceptable.”

Social media critics expressed extreme frustration. Some reported spending hours trying to get an appointment.

Mental health expert John Grohol tweeted a photo of the non-working web site with the tagline, “Massachusetts. Home to MIT, Harvard, and world-class internet startups. This is our vaccine appointment website at one point this morning.”

Tiffany Dowd, a social media influencer who advises the luxury travel industry, got to the stage of selecting an appointment time, with many appointments listed, but got a message that none were available. “To say I am angry is an understatement,” Dowd tweeted at the governor.

One person posted a gif of a dumpster fire.

Baker has pointed to the Berkshires as a model where a regional vaccine collaborative has been effective. The county has the state’s highest vaccination rate.

But Rep. Smitty Pignatelli, who represents the region, said even there the rollout is hampered by a lack of communication. He has no idea how many vaccines were distributed in the Berkshires because the regional collaborative was not told how many shots were distributed at pharmacies or nursing homes – information the state has.

Pignatelli said the state should empower local communities, noting that when the state website crashed, appointments were available through the Berkshire Vaccine Collaborative’s website. Pignatelli said Baker should not have launched the website until it was foolproof. “I want him to be more than pissed, I want him to hold people accountable,” Pignatelli said.

Baker had a response ready when asked on GBH about the criticism, saying the agony felt by many residents amid the pandemic “makes any of the rockiness those of us in public life had to deal with feel like nothing by comparison.”