The United States has held 56 presidential elections, going back to the first in 1789. And every time, we’re told that the latest one is really, really important. ¶ Just listen to this year’s Republican contenders. “I believe this is the most important election in your lifetime, no matter how old you are,”Rick Santorum told a crowd in Tulsa this past week. Former House speaker Newt Gingrich goes further, deeming this race the most crucial “since 1860.” ¶ Democrats do it, too. “This is certainly the most important election in my lifetime — not just because I’m running,” candidate Barack Obama said in 2008. And in his 2004 Democratic convention speech, John Kerry cited war and a shrinking middle class to declare that year’s contest “the most important election of our lifetime.”¶ All elections are important, no doubt, but some must be more important than others. How can we decide which are truly historic? I don’t believe there is a single, decisive yardstick, so let me suggest an array of criteria for picking the most important elections in American history — and which contest rates as the most important of all.

Was it considered especially

important at the time?

This is the stuff of immediate context. Were voters energized? Did they expect a close vote? Were the stakes deemed especially high? And immediately afterward, did the national verdict seem particularly significant?

On this score, the 2012 contest seems to be ranking fairly high, though it may seem so precisely because we’re in the middle of it. In fact, in long-term historical comparisons, this immediacy measure is tough to get a handle on. Citizens are always supposed to be interested in elections — that is democracy, after all — and hype about the stakes is, as we know, incessant.

From the available historical accounts, it might be hard to beat 1860, when a nation facing the prospect of secession and civil war put Abraham Lincoln in the White House. There’s also the close, high-turnout election of 1896, when a frenzied rally by the business community warded off the populist William Jennings Bryan. The Rutherford Hayes-Samuel Tilden election of 1876 brought a photo finish and a contested verdict. The explosive four-candidate election of 1912 (with Democrat Woodrow Wilson, Republican William Howard Taft, Progressive Party candidate Theodore Roosevelt and Socialist Eugene Debs) brought talk of an Armageddon-style political showdown by the exuberant Progressives. It is also hard to rule out 1932, when FDR bested Herbert Hoover during the Great Depression, even if that contest wasn’t close and turnout was modest.

After World War II, the measurement and analysis get better. Political scientists Steven Rosenstone and John Mark Hansen used public opinion surveys to examine the period from 1952 to 1988; they reported that the indicator of voters saying they “care a good deal which party wins” peaked with the Dwight Eisenhower-Adlai Stevenson election of 1952, during the seemingly endless Korean War. More recently, the 2004 election brought high interest, probably because of the Sept. 11 attacks and the war in Iraq, while the 2008 vote saw enormous excitement and anticipation surrounding the candidacies of Obama and Hillary Rodham Clinton.

Was the election associated with

major, long-lasting policy shifts?

Here we switch to the kind of hindsight that historians deal in: What follows from an election is what counts. Clear standouts in this regard are, once again, 1860, which was followed by the Civil War and the end of slavery, and 1932, which gave us the New Deal.

But others are worth special mention. The 1828 election ushered in the Jacksonian era, which saw the abolishment of the National Bank as well as the appalling removal of Indian tribes from their lands east of the Mississippi. The 1876 election brought the end of Southern Reconstruction. The 1912 vote gave us Wilson and his New Freedom policies, including the income tax and the creation of the Federal Reserve. And in the past half-century, the 1964 contest between Lyndon Johnson and Barry Goldwater brought the Great Society and the advancement of civil rights, while 1980 launched the Reagan revolution.

Was the election associated with major, long-lasting change in voter coalitions?

This is of special concern to political scientists, who look for long-term patterns in voting behavior, with “long-term” meaning at least one generation. Once again, 1860 and 1932 rate high: The FDR-Hoover contest boosted the Democrats for a long time, much as Lincoln’s election led to durable power for the Republicans.

Otherwise, Thomas Jefferson’s victory over John Adams in 1800 effectively ended Federalist domination, while the 1816 election saw the demise of the Federalists, period, once they had tilted to the wrong side in the War of 1812. The 1828 election brought the Jacksonian coalition of small farmers and the working class. The Democrats surged in 1876, as did the Republicans in the McKinley-Bryan election of 1896, partly thanks to the economic depressions that preceded both votes. The Republicans skyrocketed in the Warren Harding-James Cox election of 1920 because of the casualties, economic slump, strikes and general disorder brought by World War I and its aftermath. Some analysts point to a lasting Republican surge in 1952, owing possibly to the Korean War and to the simple fact that the Democrats had been in power too long.

Since 1952, no election seems to truly qualify on this score. Even though the 1980 vote gave us Reagan, by then the Republicans had been winning most presidential elections for quite a while; yet they couldn’t win the House until 1994. The GOP’s rise was episodic and gradual.

What if the other guy had won?

In a close election, would a win for the losing side have made a big difference, taking the country in a significantly different direction? It is fun to look back and play the counterfactual game.

Elections can be a lottery. A gaffe, a rainstorm in the wrong place or hanging chads can tip the outcome — and major policy differences can result. In the liberal or progressive canon, a famous lost chance was the fairly close election of 1896. Who knows what a Bryan presidency would have amounted to — new taxes, trust-busting, regulations or currency reform? Historian Gary Kornblith has written about the knife’s-edge election of 1844: Suppose that the winner that year, James K. Polk, eager for U.S. military expansion, had lost to Henry Clay, who was not? Could the seizure of half of Mexico, the expansion of slavery to the Southwestand the resulting tensions that fueled the Civil War all have been avoided?

In 1864, Union military victories in September seemed to lift the incumbent Lincoln over a Democratic Party that appeared ready to settle for peace with the Confederacy and the preservation of slavery.

And how about the photo-finish George W. Bush-Al Gore election of 2000? A President Gore would probably have reacted differently to the attacks of Sept. 11, 2001 — but how differently is far from clear. The two campaigns don’t offer obvious clues, and there is an awful lot of contingency in foreign policy, where presidents must react to challenges as they crop up. We can have hunches but not answers.

Did the campaign itself have a big

impact, independent of the result?

Elections are not just the counting of November ballots. During the months of a presidential campaign, voter opinion can be shaped as well as expressed — the whole long process can even push the nation toward a new consensus. In 1940, the Republican nomination of the internationalist Wendell Willkie left his party’s isolationist wing in the dust. The resulting Willkie-FDR campaign, relatively free of isolationism, probably helped foster national agreement on foreign policy in that scary year when the Nazis were marching and bombing in Europe. In 1948, the Republican nomination of the moderate Thomas Dewey, President Harry Truman’s platform and the marginalization of extremist third parties as the season went on seem to have nudged the country toward agreement on civil rights, the New Deal’s welfare-state programs and the prosecution of the Cold War against the Soviet Union.

On the other hand, election seasons can push toward dissent, too. In 1860, the Democratic Party broke in half, reflecting and exacerbating the regional tensions that brought civil war. And for those of us who were there, who can forget the election season of 1968? The anti-Vietnam War movement sprang to life, President Johnson bowed out, the Democratic Party self-destructed at its nominating convention in Chicago, and the populist segregationist George Wallace drew an eighth of the vote in November. That year, the election process itself seems to have contributed to national disintegration.

Did it set a landmark political

precedent?

In 1789, when George Washington was ushered into the presidency, it was a big deal that a nationwide choice of a chief executive could happen at all. Jefferson’s election in 1800 set a precedent as one national ruling party peacefully displaced another. Andrew Jackson’s election in 1828 brought mass political participation, at least among white males. Ulysses Grant’s reelection in 1872 profited from the 15th Amendment’s enfranchisement of African Americans. The Harding-Cox election of 1920 saw a doubling of eligible voters after the 19th Amendment enfranchised women. The 1960 election sent the first Roman Catholic president, Kennedy, to the White House. And of course 2008 scored two major firsts in the realms of gender and race: Clinton came close to the presidency, and Obama reached it.

Where does this leave us? What was the most important election in our nation’s history? All in all, blending these various standards, I would rank 1860 as No. 1: That year’s campaign contributed to a disintegration of the national fabric, and the aftermath included the astonishingly bloody Civil War, the abolition of slavery and the construction of a much stronger national state. I would rank 1932 at No. 2: No election of the past century has matched it for policy innovation — the New Deal — or for the lasting coalitional surge it brought to the winning party.

After those two, many of the contests I’ve listed would fight it out for the runner-up slots, with no clear ranking in sight.

It is interesting to note that the list grows lean in recent decades. The post-World War II elections of 1948, 1952, 1960, 1964, 1968 and 1980 merit mention — but the ones after that, very little. Am I being shortsighted? Possibly, but notwithstanding what we might think about it, American political life has become smoother and more stable. In our history, standout elections have tended to hinge on explosive circumstances or events — slavery and race, large wars, or uncontrollable economic disasters. (After all, there were no TARP bailouts in the depressions of 1873, 1893 or 1929.)

Without a slavery crisis, the 1860 election ceases to be consequential. No World War I means no era of Harding, Coolidge and Hoover. Without a Great Depression, there is no New Deal. No Vietnam War, no monumental 1968 campaign. In the battle for our votes, there is a lot of ghastliness back there.

These days, U.S. society is more inclusive and more prosperous. Government management of the economy is better. There is a safety net. Since the 1970s, our military enterprises have been smaller; even in the case of Iraq and Afghanistan, U.S. casualties and the share of gross domestic product going to the military were considerably lessthan in earlier wars, and there was no draft. It has been harder to rock elections out of their usual orbit, at least very far or for very long. Party clashes over taxes and spending are in lively form — but that is normal politics.

Yes, voter interest soared in 2004 and 2008, but I do not see any sign that the elections of Bush and Obama brought major, lasting changes in voter coalitions. As for significant long-term policy change, the jury is out. Possibly some of the Obama program of 2009-10 will stick and be considered historically important (health care comes to mind), but we simply don’t know yet. The signal significance of 2008 was the election of an African American to the White House — a truly historic event.

As for 2012? There may be some lasting, important policy changes to emerge from this election, but most of the time that doesn’t happen. So far in this campaign, we don’t seem to have witnessed big, energizing events, a new mood that invests the public in the outcome or signs of a clear voter mandate. In most elections, deft management of the economy and smart, prudent foreign policy are enough to ask for.

outlook@washpost.com

David R. Mayhew is Sterling professor of political science at Yale University and the author of “Partisan Balance: Why Political Parties Don’t Kill the U.S. Constitutional System.”

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