Pittsburgh ? The White House is often transformed along with its occupant. The Oval Office rug has been changed 10 times since the years before the Great Depression, from the green of Herbert Hoover to the pale gold of George W. Bush. The dark green drapes of the Franklin Roosevelt years have been replaced eight times and now are antique gold.

The rugs and drapes reflect changing fashions, and so do the wall appointments. Ronald Reagan hung a portrait of Andrew Jackson in the Oval Office and caused a flurry of commentary when he displayed portraits of Calvin Coolidge and William Howard Taft in the Cabinet Room. His successor, George H.W. Bush, replaced Coolidge and Hoover with Theodore Roosevelt. Our current President Bush has one of the many famous Rembrandt Peale portraits of George Washington hanging over the Oval Office mantle and a portrait of Abraham Lincoln near the door that leads to his study and the presidential dining room.

The two finalists hurtling toward Tuesday’s Pennsylvania primary clearly are making history; the Democrats are poised to select either the first female or the first black presidential nominee of a major American political party. But as this race works its way to its keystone climax, it is also clear that the two finalists are thinking about history as well, seeking to draw lessons from it, trying to see patterns in it.

So when the two came calling to our newspaper here in Pittsburgh last week, it seemed natural to try to gauge some historical insights from their interior-decorating preferences. Campaign aides customarily tell their candidates not to start measuring the Oval Office for curtains, but there is no aphorism that prevents an editor from asking what portraits they would place on the walls (cream/beige, for now).

The clear winner was Abraham Lincoln. Sen. Hillary Rodham Clinton of New York cited her own Illinois youth and explained, with some enthusiasm: “I just really think of him as an extraordinary human being as well as a great president.”

Lincoln was Sen. Barack Obama’s first choice. “The last Illinois president,” said Mr. Obama, who represents Illinois in the Senate. “Not very experienced.”

The senator laughed and then added: “The reason that he’s, in my mind, the first among equals is not only did he guide the country through our biggest crisis, but he never lost sight of what Americans had in common and didn’t demonize the other side. I think better than anybody (he) appealed to the better angels of our nature.

“I think his language and his spirit allowed reconciliation, and he also, I think, understood that there is a role for government to play as an active force in shaping opportunity even though he was a strong proponent of markets and … capitalism.”

Obama argued that, in the middle of the Civil War, Lincoln played an instrumental role in setting up land-grant colleges, helped stitch the continent together with the intercontinental railroad, and took steps to expand opportunity with the Homestead Act, which helped open up the West to settlement in the final third of the 19th century.

“Here’s somebody who recognized that the task of government is not to do for the American people – they’re more than capable of doing for themselves – but it is to create conditions in which people have the tools they need to succeed,” he said. “And that, I think, is the kind of spirit that we need right now.”

Besides Lincoln, Mrs. Clinton cited George Washington (“for navigating this new nation through some very challenging times”), Theodore Roosevelt (who “understood the challenge of moving from an agrarian to an industrial society”) and Dwight D. Eisenhower (who had a “real, almost visionary aspect that we often don’t think of”).

Then Clinton expressed praise for both John F. Kennedy (“for his extraordinary charisma and his ability to summon us to care about and act upon what our country needed”) and Lyndon B. Johnson (“because of his skills laying the foundation for much of what we are fighting to protect right now – Medicare and Medicaid”).

These may be, besides Mrs. Clinton’s selection of Eisenhower and Johnson, standard-issue civics-class evocations of the American pantheon. Modern American political figures seldom draw upon Martin Van Buren, Grover Cleveland and William Henry Harrison, and we would be befuddled if they did.

(Karl Rove, President Bush’s political guru, often looked to the lessons of William McKinley, partly out of admiration for the Ohio president’s success in shaking Republicans’ focus from Reconstruction to the new realities of a nation of immigrants and industry, partly because he delighted in citing an unconventional choice for inspiration. Today, of course, McKinley’s support for high tariffs might find ardent backers … in the Democratic Party.)

What is striking about the responses of both Mrs. Clinton and Mr. Obama – and about the candidates who made them, days before the Pennsylvania primary – is the understanding that leadership in the presidency combines the skills of the accountant and of the preacher. They recognize that presidential leadership is both mastery and performance.

That is what last week’s squabble about elitism and bitterness was all about – taking stock, as an accountant would do, of assets and liabilities, and then giving voice, as a preacher would do, to human emotion.

During her visit to the Post-Gazette, I asked Mrs. Clinton if the Wellesley and Yale Law School of the young Hillary Rodham were appreciably more populist than the Columbia and Harvard Law School of the young Barack Obama. She answered by saying that she was rooted in the Midwest and in its values, which was a good answer and probably a true one.

I thought about that while I was sitting in the very same chair 30 hours later, with Obama in the hot seat, arguing that many people in distressed small towns in Pennsylvania were “cynical about the possibility of change” and as a result “they then rely on those things that they can count on,” like religion and hunting traditions. It was then that I noticed that Mrs. Clinton wasn’t the only one rooted in the Midwest. Mr. Obama was in Pittsburgh, but his watch was set to Central Daylight Time.