They got the band back together.

Twenty years after Massachusetts passed landmark health care reform legislation that gave the state the highest rate of insurance coverage in the country, the leading players behind the law gathered in the same storied meeting hall where the 2006 bill was signed to celebrate their uncommon achievement.

Legislators greeted the activists who pushed them to act. Business leaders and health care administrators who worked out disagreements sat shoulder to shoulder in the audience. And underscoring what a singular feat it all was, five Massachusetts governors came together, as Gov. Maura Healey was joined by four of her predecessors, two Democrats and two Republicans, at Monday’s event at Faneuil Hall in Boston.

Against the backdrop of the dysfunctional, toxic climate that now defines Washington, the health care bill’s embrace by the state’s overwhelmingly Democratic Legislature and the Republican governor who signed it into law seems even more remarkable today.

The common cause that united them, not any differences they had, animated the bipartisan bonhomie that marked Monday’s commemoration.

“Political rivals respected each other, buried political weapons, and worked together to find solutions,” former governor Mitt Romney said from the same stage where he signed the law 20 years ago. “The political leaders who were part of this effort came to the job to get things done, not just to see what we could do to get ourselves reelected.”

The celebration came as the state faces tremendous threats to its effort to maintain near-universal coverage, and with business leaders, health care officials, and state leaders conceding that they have done little to tame runaway health care costs. The state has the highest average cost for employer-based family premiums in the country, the state Health Policy Commission reported last fall.

The crowd gave a warm welcome to Romney, who said that after his recent six years in Washington as a US senator from Utah, “I have greater appreciation for what we did here in Massachusetts.” There was no talk about serving as governor here making him feel like “a cattle rancher at a vegetarian convention,” a line he used in southern states when trying to buff up his conservative credentials in the run-up to his 2008 presidential run.

Meanwhile, Sal DiMasi, the wise-cracking Massachusetts House leader during the health care reform, who once famously quipped that he “got frostbite” from a hug the more buttoned-down Romney gave him, began a long list of tributes with high praise for the former governor.

“First and foremost, I’d like to thank Gov. Mitt Romney,” said the 80-year-old DiMasi, who has weathered life-threatening cancer as well as five years in federal prison on corruption charges. “Governor, you showed the nation what could be accomplished when you work productively and respectfully.”

Former governor Deval Patrick, who was charged with overseeing implementation of the law when he took office in 2007, echoed the theme, saying Massachusetts officials showed what “collaborating across all kinds of difference and all sorts of interests can achieve in service of the common good.”

“It was never about perfection, never about ideological or partisan purity,” Patrick said. “Never about having to agree on everything before we worked together on anything.”