WASHINGTON - During the five decades that the New Deal coalition governed national politics, from the 1930s to the 1980s, the relationship between the Democratic Party and working-class voters was an economic bond: Generations of Americans took it as an act of faith that Republicans represented the moneyed elites while Democrats stood up for the little guy.
Since 1980, that relationship has eroded and now it's in tatters. Democrats have lost significant support among the working class. They have made big gains among upper-middle-class voters.
And while social issues set the trend in motion, the party's decision in the early '90s to move away from redistributive tax-and-spend economics - a change that was crucial to winning over upper-income professional voters - has had the rather obvious effect of fraying the party's bond with blue-collar workers.
Nonetheless, many Democratic politicians can't seem to acknowledge that the rupture is based on economics. Instead, it gets variously ascribed to a backlash against civil rights and abortion rights - and especially to Republican manipulation of patriotism and religious values.
This allows Democrats to believe that their problems with the working class are mostly based on prejudices or misperceptions. All that's needed, apparently, is to clear the record on patriotism and religion, while awaiting the inevitable maturing of public opinion on racial issues and gay rights.
This view - essentially, that working-class voters are unaware of what's in their best interest - is condescending on its face. And Democratic politicians often compound the problem by dealing in stereotypes.
In 2004, presidential candidate Howard Dean vowed to sponsor a NASCAR entry and thereby win over young Southern guys with Confederate flags on their pickup trucks. Last week, Barack Obama opined that when workers don't have good jobs "they get bitter, they cling to guns or religion or antipathy to people who aren't like them or anti-immigrant sentiment or antitrade sentiment as a way to explain their frustrations."
This diagnosis didn't go down well, and Obama has apologized for his choice of words. But unlike Dean, Obama at least seemed aware that blue-collar dissatisfaction was rooted in economics.
Thirty years ago, the Democrats would have had a ready response. By pursuing redistributive programs, from make-work jobs to urban redevelopment programs to costly expansion of rural infrastructure, the Democrats provided some economic First Aid to distressed people and communities; it fell to Republicans to try to convince people facing hardships that their problems would be better improved through policies that encouraged economic growth.
For those in the throes of hardship, the choice was obvious - between tangible benefits from the Democrats and an intangible theory from Republicans. But then the tax-cut movement of the late '70s gave the GOP a way to provide some direct benefits of its own. And in 1980, Ronald Reagan carved away significant blue-collar support.
While some Reagan Democrats clearly were drawn by his hawkish foreign policy and opposition to abortion rights, they also saw benefits in his tax cuts. And when the Democrats - encouraged by leaders like Gary Hart, Paul Tsongas, and, Bill Clinton - remade themselves, they kept their liberal social positions but jettisoned their redistributive economics.
This wasn't some hidden evolution: Bill Clinton loudly and proudly proclaimed the end of the era of big government. And during the Bush years, the Democrats' main economic message has been fiscal responsibility, while decrying the unfairness of the president's tax cuts.
In this year's presidential campaign, Obama and Hillary Clinton have each targeted blue-collar voters with the same message: A promise to reopen global free-trade deals.
Each candidate has offered sweeping antitrade rhetoric, pandering to the debatable notion that global trade is primarily responsible for manufacturing woes. But the candidates' promises to ensure that trade deals include higher labor and environmental standards may not make much of a difference. There also have been some winks and nods from aides to both candidates suggesting that their rhetoric may be stronger than their willingness to force changes.
Meanwhile, neither Hillary Clinton nor Obama has promised that their plans for solving the healthcare crisis would redistribute resources to the working class. Instead, the candidates have stressed the potential savings to business. And while Obama has promised to put more money into government construction projects, it's usually just a throwaway line in his stump speech.
Democrats are relying on the fact that Republican John McCain is an unapologetic free trader to make their own, more conditional support of free trade seem like a boost to the working class.
It's unclear whether laid-off workers will perceive much comfort - let alone tangible benefits - from those policies. And unless they can offer a strong economic appeal to the working class, Obama and Hillary Clinton will have four years to grumble about the mysterious appeal of the GOP message of God, guns, and gays.
Peter S. Canellos is the Globe's Washington bureau chief. National Perspective is his weekly analysis of events in the capital and beyond.