There was a discredited president, distrusted by his own party, portrayed by even his fondest allies as a disappointing underachiever. There was an Eastern governor, decorated with breathtaking academic credentials and a star turn in the nonprofit sector, mounting a serious challenge. There was the threat of minor-party candidacies, with charismatic leadership and a core of devoted supporters who could skew the contest. It was perhaps the greatest election in American history. It was exactly a century ago.

That year, 1912, stands as a hinge in American history. It was when the Republican Party reverted from its new identity as the party of reformers back to being the party of business, when the Democrats transformed themselves from outsider social critics to insider social activists, when questions about the character of capitalism filled the air, and when the power — and limits — of personality in politics were glimpsed.

Often we view the past not so much through a mirror as through a magnifying glass — Lyndon Johnson and Barry Goldwater, the combatants from 1964, for example, seeming so much bigger and more substantial than their counterparts from our own time — but in truth the principals of Election 1912 were larger than life, arguably larger than their equivalents from Election 2012.

2012 echoes 1912

American politics rarely repeats itself, but in the few occasions it does, it sometimes happens with almost eerie century-long congruity. The elections of 1828 and 1928, for example, were both about the accessibility of the White House to outsiders, just as the elections of 1864 and 1964 both were choices between continuity and radical departure. This election in 2012 has strong echoes of 1912, with the Republican Party holding a remarkable, completely unexpected seminar, perhaps even a public hearing, about the capacities and dangers of capitalism — and about the capacities and dangers of government regulation.

Only once or twice in a generation does the country examine with such searing rhetoric and sharp-eyed judgment these kinds of fundamental questions about business and government. It has been great sport to argue that this year’s early political contests have been dominated by farcical characters. But no one can plausibly argue that the contests themselves have been about peripheral issues. These are the bedrock questions of a democracy and of a mature economy.

Such were the issues a century ago, when President William Howard Taft veered from the one true progressive, reformist religion of the GOP predecessor who hand-picked him, Theodore Roosevelt. Both Taft and Roosevelt were vast, important departures from the Republican presidents who preceded them, smaller men like William McKinley (an unlikely role model for George W. Bush to have chosen) and Chester A. Arthur (nobody’s role model), and from the Republican presidents who would succeed them, commerce-oriented men like Warren G. Harding and Herbert Hoover.

Roosevelt was so alienated from his onetime protege that he broke, like a bull moose, from the Republican Party he had transformed and mounted an independent candidacy. The Democratic nominee was the misty-eyed idealist from Princeton, Woodrow Wilson, perhaps the greatest reformer to cling to the odious racial values of the segregated South. Also on the ballot was Eugene V. Debs, who had played a cameo role in many of the signal struggles of the time, including the Pullman Strike, and would later help to form the Industrial Workers of the World, known as the Wobblies. Debs would draw almost a million votes.

Using centralized power

These were major, enduring figures on the American scene. “Theodore Roosevelt and Woodrow Wilson invented the activist modern presidency,” Bard College political scientist James Chace wrote in the authoritative account of the 1912 election. “TR’s commitment to use Hamiltonian means to achieve Jeffersonian ends was not unlike Wilson’s use of executive power to promote free competition that would prevent big business from stifling local economies. Their legacy was the use of centralized power to create greater democracy.”

That is no mere achievement, nor an irrelevant aspect of our politics today, for in the wake of the bruising Florida primary, the very existence of centralized power and the definition of greater democracy once again are at the heart of American politics.

President Barack Obama may be, as his onetime allies on the left believe, a reluctant progressive, but he remains firmly in the Theodore Roosevelt camp, as his December 2011 journey to Osawatomie, Kan., the site of TR’s “New Nationalism” speech of 1910, vividly demonstrated. Though the president disavowed “a view that says we should punish profit or success or pretend that government knows how to fix all society’s problems,” in Kansas as in the capital, he believes in a large regulatory role in American commerce.

And though the Republicans are engaged in a vital debate about business and responsibility, the prevailing GOP ethos is deep skepticism about regulation and devout conviction that centralized power is inimical to greater democracy.

But the role that former Speaker Newt Gingrich is playing — his remorseless critique of former Gov. Mitt Romney’s years at Bain Capital standing as a symbol of a new stream of business skepticism within the modern Republican Party — does have historical antecedents.

After the election a century ago, the Republicans, as University of Wisconsin historian John Milton Cooper Jr. put it in his classic “The Warrior and the Priest,” a dual biography of Roosevelt and Wilson, “reverted to pre-1912 patterns.” But a strain of business skepticism, personified by figures with GOP roots such as Sens. Robert M. La Follette, George W. Norris, and William E. Borah, endured for a time.

Repeat of history?

Gingrich, like Roosevelt, may not have sorted out whether he is, in the formulation the late Yale historian John Morton Blum developed for TR, a conservative radical or radical conservative. Some days he is more the one, some days more the other, and some days the two converge in a fantastic melange never before seen on the American political stump.

And though the questions he is posing about Romney’s business experience are designed to achieve a narrow goal — to advance his candidacy and diminish Romney’s — Gingrich nonetheless has had a broad and important effect, changing the dynamic of the 2012 race, providing it with echoes from the 1912 race on the right to match those Obama set in motion on the left, and perhaps setting the Republican Party, maybe even setting all of American politics, on a new course. It is a rare primary fight that does so much.