Josh Zeitz has taught American history and politics at Cambridge University and Princeton University and is the author of Lincoln’s Boys: John Hay, John Nicolay, and the War for Lincoln's Image. He is currently writing a book on the making of Lyndon Johnson’s Great Society. Follow him @joshuamzeitz.

Since last week, many Republicans have been feeling singularly nostalgic for November 1928, and with good reason. It’s the last time that the party won such commanding majorities in the House of Representatives while also dominating the Senate. And, let’s face it, 1928 was a good time.

America was rich—or so it seemed. Charles Lindbergh was on the cover of Time. Amelia Earhart became the first woman to fly across the Atlantic. Jean Lussier went over Niagara Falls in a rubber ball (thus trumping the previous year’s vogue for flagpole sitting). Mickey Mouse made his first appearance in a talkie (“Steamboat Willie”). Irving Aaronson and His Commanders raised eyebrows with the popular—and, for its time, scandalous—song, “Let’s Misbehave,” and presidential nominee Herbert Hoover gave his Democratic opponent, Al Smith, a shellacking worthy of the history books.


The key takeaway: It’s been a really, really long time since Republicans have owned Capitol Hill as they do now.

But victory can be a fleeting thing. In 1928, Republicans won 270 seats in the House. They were on top of the world. Two years later, they narrowly lost their majority. Two years after that, in 1932, their caucus shrunk to 117 members and the number of Republican-held seats in the Senate fell to just 36. To borrow the title of a popular 1929 novel (which had nothing whatsoever to do with American politics): Goodbye to all that.

A surface explanation for the quick rise and fall of the GOP House majority of 1928 is the Great Depression. As the party in power, Republicans owned the economy, and voters punished them for it. In this sense, today’s Republicans have no historical parallel to fear. Voters—at least a working majority of the minority who turned out last week—clearly blame Barack Obama for the lingering aftershocks of the recent economic crash.

But what if the Republicans of 1928 owed their demise to a more fundamental force? What if it was demography, not economics, that truly killed the elephant?

In fact, the Great Depression was just one factor in the GOP’s stunning reversal of fortune, and in the 1930 cycle that saw Republicans lose their commanding House majority it was probably a minor factor. To be sure, the Republicans of yesteryear were victims of historical contingency (the Great Depression), but they also failed to appreciate and prepare for a long-building trend—the rise of a new urban majority comprised of over 14 million immigrants, and many millions more of their children. Democrats did see the trend, and they built a majority that lasted half a century.

The lesson for President Obama and the Democrats is to go big—very, very big—on immigration reform. Like the New Dealers, today’s Democrats have a unique opportunity to build a majority coalition that dominates American politics well into the century.

***

For the 1928 GOP House majority, victory was unusually short-lived. About one in five GOP House members elected in the Hoover landslide served little more than a year and a half before losing their seats in November 1930.

On a surface level, the Great Depression was to blame.

The stock market crash of October 1929 destroyed untold wealth. Shares in Eastman Kodak plunged from a high of $264.75 to $150. General Electric, $403 to $168.13. General Motors, $91.75 to $33.50. In the following months, millions of men and women were thrown out of work. Tens of thousands of businesses shut their doors and never reopened.

But in the 1920s—before the rise of pensions and 401Ks, college savings accounts and retail investment vehicles—very few Americans were directly implicated in the market. Moreover, in the context of their recent experience, the sudden downtick of 1929-1930 was jarring but not altogether unusual. Hoover later recalled that “for some time after the crash,” most businessmen simply did not perceive “that the danger was any more than that of run-of-the-mill, temporary slumps such as had occurred at three-to-seven year intervals in the past.”

By April 1930, stocks had recouped 20 percent of lost value and seemed on a steady course to recovery. Bank failures, though vexing, were occurring at no greater a clip than the decade’s norm. Yes, gross national product fell 12.6 percent in just one year, and roughly 8.9 percent of able-bodied Americans were out of work. But events were not nearly as dire as in 1921, when a recession sent GNP plunging 24 percent and 11.9 percent of workers were unemployed.

In fact, Americans in the Jazz Age were accustomed to a great deal of economic volatility and risk exposure. It was the age of Scott and Zelda, Babe Ruth, the Charleston, Clara Bow and Colleen Moore—the Ford Model T and the radio set. But it was also an era of massive wealth and income inequality. In these days before the emergence of the safety net—before unemployment and disability insurance—most industrial workers expected to be without work for several months of each year. For farm workers, the entire decade was particularly unforgiving, as a combination of domestic over-production and foreign competition drove down crop prices precipitously.

In hindsight, we know that voters in November 1930 were standing on the edge of a deep canyon. But in the moment, hard times struck many Americans as a normal, cyclical part of their existence.

Unsurprisingly, then, many House and local races in 1930 hinged more on cultural issues—especially on Prohibition, which in many districts set “wet” Democrats against “dry” Republicans—than economic ones.

If the Depression was not a singular determinant in the 1930 elections, neither had Herbert Hoover yet acquired an undeserved reputation for callous indifference to human suffering. Today, we think of Hoover as the laissez-faire foil to Franklin Roosevelt’s brand of muscular liberalism. But in 1930, Hoover was still widely regarded as a progressive Republican who, in his capacity as U.S. relief coordinator, saved Europe from starvation during World War I. When he was elected president, recalled a prominent journalist, we “were in a mood for magic ... We had summoned a great engineer to solve our problems for us; now we sat back comfortably and confidently to watch problems being solved.”

In 1929 and 1930, Hoover acted swiftly to address what was still a seemingly routine economic emergency. He jawboned business leaders into maintaining job rolls and wages. He cajoled the Federal Reserve System into easing credit. He requested increased appropriations for public works and grew the federal budget to its largest-ever peacetime levels. In most contemporary press accounts, he had not yet acquired the stigma of a loser.

Still, in 1930 Hoover’s party took a beating. Republicans lost eight seats in the Senate and 52 seats in the House. By the time the new House was seated in December 1931, several deaths and vacancies resulted in a razor-thin Democratic majority.

If the election was not exclusively or even necessarily about economics, the same cannot be said of the FDR’s historic landslide two years later. As Europe plunged headlong into the Depression in 1931 and 1932, the American banking and financial system all but collapsed. With well over 1,000 banks failing each year, millions of depositors lost their life savings. By the eve of the election, more than 50 percent of American workers were unemployed or under-employed.

In response to the crisis, Hoover broke with decades of Republican economic orthodoxy. He stepped up work on the Boulder Dam and Grand Coulee Dam (popular lore notwithstanding, these were not first conceived as New Deal projects). He signed legislation outlawing anti-union (“yellow dog”) clauses in work agreements. And he chartered the Reconstruction Finance Corporation, a government-sponsored entity that loaned money directly to financial institutions, railroads and agricultural stabilization agencies, thereby helping them maintain liquidity. The RFC was in many ways the first New Deal agency, though Herbert Hoover pioneered it. Even the editors of the New Republic, among the president’s sharpest liberal critics, admitted at the time, “There has been nothing quite like it.”

Despite his proactivity, Hoover could not save himself, or his party, from defeat. For one, he was a dreary candidate, ill-suited to motivating his countrymen in times of crisis. “If you put a rose in his hand,” quipped the sculptor Gutzon Borglum, “it would wilt.” More fundamentally, amid so much human suffering, Democrats had to do very little to win. They were of no mood to offer constructive counter-solutions, as doing so would shift responsibility to Congress, where they controlled the House. Belying his own progressive tenure as governor of New York, Roosevelt actually ran at Hoover from the right, deriding his profligate spending (FDR pledged to trim the budget by 25 percent). He warned that Republicans were dangerously “committed to the idea that we ought to center control of everything in Washington as rapidly as possible.”

In November 1932, voters overwhelmingly repudiated the recently triumphant GOP, denying Hoover a second term and consigning congressional Republicans to a hopeless minority status in both chambers.

The Depression had much to do with these events, but so did a less discernible trend: immigration. Here is where the history gets interesting for today’s Democratic party.

***

With hindsight, Republicans probably should have realized that they were about to lose their national majority, though it is easy to understand why they didn’t. Between 1860 and 1928, the GOP had won 14 of 18 presidential elections. For roughly two-thirds of that time, it also controlled the House of Representatives. Why would anyone imagine the party’s winning streak was about to end?

Yet between 1920 and 1930, over 17 million new voters came of age; in the following decade, well over 20 million more would join the rolls. All together, the number of voters participating in presidential elections jumped by more than 90 percent in this relatively short time period.

The vast majority of these new voters were immigrants and their children. They were urban, Jewish and Catholic, predominately from Eastern and Southern Europe, and in many quarters, old-stock Americans scarcely regarded them as white. Aided by the steady northward and urban migration of African Americans, whose allegiance to the party of Lincoln waned appreciably over the course of the New Deal era, these trends created a rising Democratic majority. In heavily ethnic wards in Chicago, only one-third of adult residents were eligible to vote in 1920. By 1930, two-thirds were eligible.

Even in the wake of their triumph in 1928, Republicans should have seen the writing on the wall. Whereas in 1924 they enjoyed a 1.3 million-vote plurality in the nation’s dozen largest cities, in 1928 the Democrats won a small plurality of 210,000 votes. In 1936, Democrats swept the big cities by a whopping 3.47 million votes. It was a pattern that sustained the Democratic Party for the next 50 years.

In large and medium-sized cities that Republicans carried comfortably in 1928—Baltimore, Pittsburgh, Chicago, San Francisco, Flint, Los Angeles, Akron, Des Moines, Seattle, Duluth, Canton, Spokane, Detroit, Youngstown—they were now losing by two-to-one margins.

Writing many years later, the noted political demographer Samuel Lubell surmised that the “real revolutionary surge behind the New Deal lay in this coupling of the depression with the rise of a new generation, which had been malnourished on the congestion of our cities, and the abuses of industrialism. Roosevelt did not start this revolt of the city. What he did do was to awaken the climbing urban masses to a consciousness of the power in their numbers.”

To be sure, the New Deal majorities were never pre-determined. History is made in equal parts by contingency, design and subtle demographic, environmental and economic forces. The Great Depression was a contingent event; the New Deal was born of human design. Demographic trends were a structural ingredient of change. For decades, urban Democratic machines throughout the north and west worked hard at cultivating new Americans, welcoming them into their tent and offering them a stake at citizenship. FDR assiduously courted white ethnic voters (while by her actions, his wife, Eleanor, welcomed black voters into the party). The deep and resonant bond that new Americans felt with the New Deal was built by a decade’s worth of fireside chats and local electoral rallies, and by an activist policy agenda that helped millions of working families survive an unforgiving decade. Democrats saw an opportunity, and they labored to seize it.

In the wake of last week’s elections, there has been much hand-wringing over Democrats’ abysmal showing among these white, working-class voters. It’s a problem that surely demands some solution. But history points in a more promising direction.

As early as 1910, more than 50 percent of all public school students in the nation’s largest cities had at least one foreign-born parent. These second-generation kids were the time bomb that exploded in 1930.

Now look at today. According to the Brookings Institution, as recently as 2012, the toddler (that is, under age 5) population of 14 states was already majority-minority, meaning white toddlers comprised less than half of their cohort. That figure includes blue states like New York and New Jersey, but also deep-red states like Arizona (36.9 percent white), Georgia (43.1 percent white) and Texas (31.1 percent white). In Mississippi—yes, Mississippi—the population under 5 is now majority-minority. These pre-school children and their older siblings are the new voters of 2016, 2020 and 2024.

Democrats currently expend a great deal of money and effort to ensure that in off-year elections, non-white turnout is closer to its 2012 levels (28 percent) than its 2014 levels (25 percent). Six years from now—when Democrats have an opportunity to sweep state houses in a presidential election cycle and a census year, and thereby effect congressional redistricting—these targets will seem laughably small.

The choice for Democrats is stark: actively embrace executive action on immigration, knowing that it will cause a firestorm in Congress and potentially more slippage with working-class whites—or wait.

History would suggest that there is little upside to waiting. Waiting gives savvier Republicans like Marco Rubio and Jeb Bush—who take a longer view than many of their colleagues—a chance to make deep and lasting inroads with Latino voters (who are, after all, a tremendously diverse population). Waiting allows Republicans to continue their courtship of second-generation Asian Americans, who are equally diverse. Waiting means doubling down on a diminishing portion of the electorate. As in 1930, the future is with a winning coalition of new Americans, African Americans and white progressives.

For new Americans of the New Deal era, the Democratic Party offered both inclusion and rescue from a dire emergency (economic insecurity). For countless new Americans of 2014, executive action on immigration reform offers immediate relief from an emergency no less profound (the insecurity of statelessness). As was the case then, today, a bold agenda can build a lasting majority.

Franklin Roosevelt, who banished the GOP to political wilderness for a half-century, once said that it is “common sense to take a method and try it. If it fails, admit it frankly and try another. But above all, try something.” Millions of new Americans who desperately required economic relief and who hungered for inclusion came to appreciate the innovative, provisional and welcoming spirit of the New Deal.

Today, many millions of undocumented Americans are living in the shadows. But they have brothers, sisters, cousins, spouses and children who enjoy legal status and will soon be eligible to vote. For Democrats, the history lesson is simple: take a method and try it.