This week, the Kansas Senate voted by a wide margin to expand the state’s Medicaid coverage. A majority of Democrats supported the bill, as might be expected, but so did a majority of Republicans. That the vote was both bipartisan and decisive is a modest but promising sign for the future of public health insurance. But the vote had an added significance because it took place in Kansas. For the six years that Sam Brownback has been Governor, the state has been the scene of what may be the nation’s most extreme experiment in conservatism. The Medicaid vote capped an extraordinary year-long turn against Brownback, in which many of his allies in the legislature were defeated in primary and general elections, and, in the legislative session now coming to a close, his budget and priorities were rejected. The political history of the past quarter century has been one of deepening polarization. The reaction in Kansas suggests that it is still possible for a party to go too far—that there is still a center in American life which may yet hold.

Brownback, who has a law degree from the University of Kansas, is possessed of a low-key personal style and a high-intensity conservative politics. He has been the defining figure in Kansas political life for two decades, since he won Bob Dole’s Senate seat in the 1996 election. In the mid-aughts, when evangelical conservatives were understood to be the country’s most powerful political bloc, Brownback had seemed a plausible representative for the G.O.P.’s future—a rigid social conservative who found some ways to appeal to moderates. He made increasing American aid to Africa his cause, and cited the example of William Wilberforce, the Christian abolitionist who helped lead the campaign to end the slave trade in the British Parliament, so often that there was a rash of editorials about the rise of “Wilberforce Republicans.” But national politics grew more liberal and optimistic, and after a brief bid for the 2008 Republican Presidential nomination Brownback returned to Kansas, where he won the Governor’s office in 2010. In his first term as Governor, he focussed on a different kind of problem. People were leaving his state for “faraway places that entice our children to abandon the communities that nurtured them,” he wrote, in 2012. “I don’t have oceans and I don’t have mountains,” he pointed out to an interviewer last year. “Just got mountains of grain.”

Brownback decided to remake Kansas by radically cutting taxes, an experiment to draw new business and people to the state. “We can no longer afford to view our current economic crisis as something distinct and apart from the crisis of family and community decay,” he wrote in an op-ed, in 2012. Brownback persuaded the legislature to adopt budgets that would eventually eliminate taxes on three hundred and thirty thousand small businesses, and cut the state’s top income-tax rate by a third. Brownback chose to opt out of Obamacare’s Medicaid expansion, which denied coverage to more than seventy-five thousand Kansans.

But the flight out of Kansas did not reverse, and as revenues diminished even basic state functions began to erode. Budget shortfalls were so severe that Kansas turned to raiding its highway-construction fund, which meant that highways were not repaired. Without Medicaid patients, a large rural hospital in Independence had to close. Public schools saw their performance on standardized tests decline, as the state contributed less to their budgets; the Kansas Supreme Court held in two different cases that the state’s underfunding of education was in violation of its own constitution. Brownback became the least popular governor in the country—last September, his approval rating was at twenty-three per cent. Seven separate organizations were founded with the goal of electing moderates, and one of them, the Save Kansas Coalition, persuaded the four living former governors of the state—two Democrats and two Republicans—to denounce Brownback and endorse moderate candidates for legislative offices. Mike Hayden, a former Republican Governor, said that Brownback and his allies “should be ashamed” of what their tax cuts had done to the state. “We virtually don’t have a penny in our pocket,” Hayden said. “The experiment is failing.”

In the Republican primaries last year, moderates ousted more than a dozen Brownback supporters, most of them explicitly declaring their opposition to the Governor. In the general election, more than a dozen more Brownback Republicans lost to Democrats. When the legislature reconvened, in January, a moderate coalition rejected Brownback’s budget and voted to expand Medicaid. (Yesterday, Brownback vetoed the legislation; the moderates may be a few votes short of overriding him.) At a forum after the election, the executive director of the Kansas Republican Party suggested that there were “some voters who were anti-Brownback and there were others whose main motivation was they didn’t like the status quo.” He conceded, “They had this uncomfortable feeling about Kansas.”

State legislative elections receive little attention, but their stakes are high, making them a good target both for lobbyists and for ideological factions. Harvard’s Theda Skocpol has found that the best predictor of whether a state legislature voted to curb public-employee bargaining in 2011 was not public opinion within the state but whether the Koch-backed group Americans for Prosperity, which was pushing the issue, had a paid staffer there. In Kansas, legislators make less than twenty thousand dollars each year, which may mean that candidates tend toward the committed fringes. In 2011, a Brownback ally in the legislature named Virgil Peck said, about a bill proposing that feral hogs be shot from helicopters, “Looks to me like, if shooting these immigrating feral hogs works, maybe we have found a solution to our illegal-immigration problem.”

The revolt of the Kansas moderates has some of the feel of a social restoration, in which small-town institutionalists reclaimed Republican politics from the ideologues who had taken over. Peck was beaten in the Republican primary by a retired Air Force commander. A school superintendent in Stafford beat a more conservative incumbent; so did a retired school superintendent from Tonganoxie. The moderate coalition that voted to expand Medicaid coverage was led by a retired anesthesiologist, Republican Barbara Bollier, who had been kicked off the Health Committee when the State Assembly was in more radical hands. Last week, shortly after the vote to expand Medicaid coverage, the State Senate passed a resolution condemning pornography. That seemed like a good hint at where Kansas politics might go, guided by the remnant faction of religious conservatives and the rising one of school administrators.

For all its excess, the Brownback era obeyed a certain logic, which also helped fuel the rural support for the Trump campaign. If you believed that your home was under existential threat, then an extreme politics made sense. In 2015, the Times Magazine published a moving story by Chris Suellentrop, a journalist and Kansas native, whose uncle, a state legislator with a serious and temperate disposition, had joined the Brownback movement. Gene Suellentrop was sensitive to his fellow-Kansans’ plight. Without an aggressive effort like Brownback’s to draw business and attention, he told his nephew, “everyone else will see us as flyover country.” In retrospect, voters’ perceptions of the state’s precariousness and Brownback’s radical politics acted as mutual accelerants. The question now is whether those levers can act in reverse—whether moderate politicians can persuade residents that no social precipice is near, that Kansas is not dying.