The increasing vitriol of the Democratic presidential WrestleMania shouldn’t distract from the opportunity before progressives. The election this year has the potential to be not simply a change election but a sea-change election, one that marks the end of the conservative era that has dominated our politics for nearly three decades. It could be the progressive equivalent of the conservative triumph of 1980.

In 1980 Ronald Reagan, the self-described “movement conservative,” took the White House from incumbent Jimmy Carter while Republicans picked up thirty-four seats in the House and gained control of the Senate, sweeping out liberal stalwarts like George McGovern and Frank Church. The Democratic majority in the House stood aside as Reagan slashed taxes and doubled the military budget in peacetime. He fired striking air-traffic controllers, declaring open warfare on unions. He surrendered the war on poverty, pushed to deregulate finance and rolled back environmental, consumer and workplace protections. Government, he announced, is the problem, not the solution.

Despite his subsequent deification by conservatives, Reagan was hardly a flawless candidate. He was widely scorned as an “amiable dunce,” in the words of Clark Clifford, while primary opponent George H.W. Bush branded Reagan’s supply-side ideas “voodoo economics.” Nor did voters experience a wholesale shift of attitudes against liberalism. Pluralities of Americans opposed Reagan on civil rights, abortion, the Equal Rights Amendment and military spending. Polls showed no dramatic increase in self-identified conservatives. Voters were repudiating Carter and throwing the bums out of Washington, not embracing conservatism. Key to that was a dismal economy–double-digit inflation, high unemployment, soaring gas prices–plus troubling events abroad, including the Soviet Union’s invasion of Afghanistan and Iran’s seizure of American hostages.

While voters hadn’t turned right, the right was on the march–and driving the debate within the Republican Party. The Moral Majority mobilized evangelicals; the Committee on the Present Danger trumpeted the mythic “window of vulnerability” in the face of the alleged Soviet threat. Corporations had been gearing up their offensive against government regulation and unions. The Heritage Foundation and other conservative think tanks were leading an attack on liberalism. At the same time, liberal movements seemed exhausted. Stagflation confounded liberal economists. Carter was embracing deregulation, military buildup, covert war in Afghanistan. His retreats and failures split Democrats, leading Ted Kennedy to challenge him in a bitter primary battle. The country was looking for change.

As this year’s election approaches, the parallels to 1980 are striking. The economy is in a recession. Gas is headed to $4 a gallon. Incomes aren’t keeping up with the cost of basics. Housing prices are cratering. Once again, the economy is the number-one issue. The failure at home mirrors the Iraq debacle abroad, which consumes $10 billion a month while alienating us from allies and eroding our security. The Bush Administration simply ignores the clear and present danger of catastrophic climate change. The public has turned against the Administration. Gallup polls show that only 27 percent of Americans are satisfied with how things are going.

Progressives are driving the Democratic presidential candidates to bolder positions against the war, for universal healthcare, for investment in new energy, against corporate trade and tax strategies. and the blogosphere have brought new energy, resources and volunteers into the process. An embattled and divided labor movement has revitalized its political program. New voters are mobilizing in the Democratic primaries.

And conservatism is exhausted and divided. The neocons are discredited, and the country clubbers disdain the fundamentalists. Main Street conservatives are appalled by the corruption and incompetence of the Bush Administration. Declining wages and the housing bust confound conservative economics. As in 1980, people are looking for change.

There are, of course, major differences between 1980 and 2008. Bush is not on the ballot, as Carter was, although John McCain seems intent on continuing Bush’s policies–on the war, on taxes, on trade and on deregulation. Conservatives are in disarray, but the corporate lobby isn’t. We’re likely to see hundreds of millions spent by insurance companies, drug companies and others in the fall elections. Perhaps the largest difference is that neither Barack Obama nor Hillary Clinton is a movement progressive the way Reagan was a devoted movement conservative. If voters once more decide to throw the bums out, neither may be as bold as Reagan was in claiming an ideological mandate and defining a fundamentally new course.

Progressives must learn what conservatives came to understand after 1980: that a sea-change election doesn’t take place on election day. Conservatives were frustrated as Reagan ignored their social agenda, abandoned Social Security privatization and negotiated with Gorbachev. They found it necessary to sustain an independent movement capacity, to push ideas and to hold politicians, Democrats and Republicans, accountable.

Like 1980, 2008 is likely to be a close, bitterly contested presidential election. But if the economy continues to decline and the costly war continues, Democrats will have a chance to capture the White House and greater majorities in both houses with a mandate for change. Then progressives will find, as conservatives found under Reagan, that the real struggle begins. For that, progressives will have to expand the agenda, build grassroots and netroots power independent of the Administration and the party, and organize to hold politicians of both parties accountable for supporting the changes this country so desperately needs.