CHARLOTTE, N.C. - We campaign in poetry, Mario Cuomo used to say, but we govern in prose.
This was how the then-New York governor explained the gap between his soaring speeches and the more prosaic product of his government, when the springtime of campaign hopes succumbed to the winter of governing discontent.
That was a generation ago. But it is a pithy summary of Barack Obama's challenge as he goes before his convention this week.
President Barack Obama
There are a lot of very angry people in the country, out of work or living on less. But anger is not the dominant political sentiment among the voters likely to swing this presidential election.
It is, instead, disappointment.
"There's absolutely a sense of disappointment among a large subset of Democrats," said David Segal, a former Rhode Island state legislator who now runs an organization that lobbies for Internet freedom and civil liberties.
The Romney-Ryan team astutely recognized the discontent and tried to package the sentiment at the Republican convention last week. The purpose was to peel away voters who were proud of their vote for Obama four years ago and are disappointed now by the state of the country he has been leading ever since.
"The president hasn't disappointed you because he wanted to," Romney said in his acceptance speech. "The president has disappointed America because he hasn't led America in the right direction."
As the challenger, Romney has the easier task. He gets to campaign in poetry. But Obama must now explain the governing prose of the last four years.
That is a very hard job, even for a campaigner as capable as Obama. The country on its face is not in great shape. The last president to win re-election with unemployment over 8 percent was Franklin D. Roosevelt. (It was 16.6 percent when FDR was re-elected in 1936, down from 24.9 percent when he was first elected in 1932.)
A key part of Obama's central argument is that, without him, these last four years would have been worse. There is considerable evidence this is true. A study by the congressional budget office says unemployment could have soared near 12 percent (instead of the peak of 10 percent) without the economic stimulus and other rescue measures Obama succeeded in passing.
But it's a hard sell to compare what a report says and what palpably is. Modern American sound-bite politics resist subtle what-ifs or might-have-beens. The template of modern presidential campaigning was a simple yes or no question from the master, Ronald Reagan. Romney wants voters to answer Reagan's simple question: Are you better off now than you were four years ago? Obama wants to change the question: Are you better off now than you would have been without me?
"It takes many more months for an incumbent to develop a credible defense of a half-full glass than it takes a challenger to remind people that the president promised to fill the half-empty glass all the way," said Samuel Popkin, a political scientist who has given message advice to several Democratic presidents and candidates.
David Plouffe, one of Obama's key strategists, went on TV Sunday to explain that Obama should be re-elected because he would do more than just finish the job of pulling America out of the recession. "We're going to explain to the American people and the middle class of this country how we're going to continue to recover, but do more than just recover from the recession, to build an economy from the middle out."
Plouffe no doubt knew what he meant by the phrase "from the middle out." Presumably, it has something to do with the difference between "trickle-down" economics and middle-class economics. But whatever it means, it is a more difficult message to get across than 2008's "Yes, we can."
Politics is always about comparisons and expectations. Few events in American political history sent expectations soaring higher than the new fact of Obama's election. But those raised expectations collided with the reality of a sour economy. Turning the welter of governing prose back into campaign poetry now is tricky.
On Monday, Joe Biden took a shot, amplifying a line that's been kicking around for days. "You want to know whether we're better off? I got a little bumper sticker for you," he said. "Osama bin Laden is dead and General Motors is alive." The Romney campaign jumped all over him for suggesting people were better off at a time when unemployment is still high and gas prices have doubled.
Biden's quip and the reaction to it point back to a central question: How well does Obama actually grasp his own plight?
There was clearly a period when he did not, when Democrats worried he would be a one-term president because he was not getting the problem. At one point, he said the problem was that he had not communicated well enough. "Every politician who gets in trouble thinks it's how they are saying things instead of what they're saying," Paul Begala, an adviser to Bill Clinton, said after they left office in 2001.
But Obama seems more focused now on doing what is needed to keep his job. He has reconciled with Bill Clinton, no small task, and at times now seems to be running on Clinton's economic record rather than his own, which makes political sense - if the public will buy it.
Yet even now, there are moments when it isn't clear if Obama's campaign fully grasps the challenge.
Aboard Air Force One on Saturday, Jen Psaki, the campaign spokeswoman, said Romney had more at stake in his convention than Obama does at his because "the American people know a lot more about the president than they know about Mitt Romney."
Actually, it is precisely because the country knows so much about Obama that he has the higher hill to climb. That's the downside of being the incumbent. It will take more than Joe Biden's bumper sticker for Obama to assuage two very different groups of disappointed voters - liberals who wish Obama had done more and swing voters who wish what he had done had worked more.
After trying to position himself as a conciliator and a mediator, Obama in recent months has been more confrontational with Congress and moved unilaterally on key issues designed to appeal to the base of the Democratic party - endorsing gay marriage, for example, and suspending deportation of young immigrants brought here illegally by their parents as children.
Those steps may help mitigate disappointment by re-energizing disillusioned liberal segments of the Democratic party. Romney's selection of Paul Ryan as his running mate is helping, too, and in the end liberal voters don't have many other places to go (although staying home would be a problem for Obama).
The middle is a different story. Much of the Republican convention was an embedded appeal to swing voters that it was okay to have voted for Obama and now reconsider. In effect: They were seduced, and now it's reality time.
"Let's put the poetry aside," said Artur Davis, a 2008 Obama supporter who switched to the Republican Party and spoke this year at its convention. And that comment illustrates precisely why an incumbent's road is harder. The very elegance of Obama's 2008 campaign has become one of his major liabilities in 2012.
That means a recalibration, and this week is the moment to see if he can be a different kind of candidate. The test now is this: Four years on from the poetry that delivered Barack Obama to the White House, can he find a voice that makes the cadence of governing prose compelling enough to keep his job?
Michael Oreskes, a veteran political reporter and editor, is senior managing editor for U.S. news at The Associated Press.