The White House has been cycling through catchphrases since announcing his reelection bid a year ago: Winning the Future, We Can’t Wait, An America Built to Last, An Economy Built to Last, A Fair Shot.

They seem to be looking for one to resonate — and the constant unveiling of new ones suggests that so far, none of them have. To communications experts, the kaleidoscope of slogans is the latest reflection of the difficulties finding and marketing a message that Obama has faced almost since his inauguration — another challenge that came with the shift from insurgent outsider to sitting president.

“He’s all over the place,” said Bruce I. Newman, the Bill Clinton brand-messaging adviser whose “Bridge to the 21st Century” helped define Clinton’s 1996 reelection campaign.

Yes, a slogan is just a few words for the background of campaign lit and stump speeches. But its importance, Newman explained, shouldn’t be understated.

“That becomes the branding of the whole campaign,” he said. “That becomes the anchor to bring together disparate voter segments. It’s the glue, if you will.”

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An Obama aide said all the lines the president has rolled out so far were around specific governing initiatives and not intended to be campaign slogans, and the GOP primarieshave yet to settle on a candidate.

Campaign spokesman Ben LaBolt said that though there may not be a slogan yet, there has been a focus on a singular theme.

“The President is working to ensure that our economy is built to last — where hard work and responsibility are rewarded, everybody does their fair share, and everyone from Main Street to Wall Street plays by the same set of rules. Mitt Romneyhas doubled down on the same policies that led to the economic crisis — he believes that we can just cut our way to prosperity and promotes outsourcing, loopholes and risky financial deals that put the security of the middle class at risk,” LaBolt said in a statement, nodding at the “fair shot” idea the president’s been hitting often since his Osawatomie, Kan., speech in December.

But Newman and others agree: The window for Obama to settle on a strong — and consistent — slogan is closing, no matter the continuing Republican primary campaign. Ronald Reagan locked down “Morning in America” in May 1984, leaving a full six months for his campaign to hammer home the message before the election.

“The thing that made it effective was that they had it up early,” said Michael Goldman, a Democratic communications consultant whose past clients include Michael Dukakis and the late Sen. Ted Kennedy. “Before the Democrats had even nominated [Walter] Mondale, he had already made that the thematic of his campaign.”

To date, Obama and his advisers have largely been defining themselves through contrast messaging — senior adviser David Plouffe called the GOP field a “clown show,” and Obama’s been casting of himself as the sober voice arrayed against irresponsible and hapless opponents.

Their options, though, are limited: Many of Obama’s biggest achievements — health care reform, financial reform, the stimulus package — are deeply divisive. The ones that are the most widely popular — the killing of Osama bin Laden and the ending of the Iraq War — are foreign policy notches that don’t have much to do with the economy, which polls consistently show is the top concern among voters right now. And the economy is still the source of too much anxiety to go the Morning-in-America route, said Democratic strategist James Carville.

“I think every instinct is to run on a version of that. Unfortunately, they can’t. I don’t think the public is with them on that,” Carville said. “They’re caught between that which they would love to do and that which they can’t do.”

The campaign spent hundreds of thousands of dollars recently on “The Road We’ve Traveled,” a 17-minute film that attempts to remind people of what Obama has done and cast a more favorable light on accomplishments unpopular in the polls. But that title doesn’t look forward. It doesn’t say what he will do if reelected or even crystallize his record in a way that’s clear and on the offensive.

Sympathetic Democrats lament a familiar problem from Obama’s first three years in office.

“I think that they were talking about everything they were doing as president,” Democratic pollster Celinda Lake said. “That meant their message was very diffuse.”

Lake said their efforts have been improving in recent months, and Obama’s placement in the polls reflects that.

”Now they are talking about only a few things, and it’s working,” she said.

But Carville — who helped frame Bill Clinton’s 1992 campaign around “It’s the economy, stupid” — said there’s still a distance to go to improve the messaging on the core issue of the campaign.

“I think they sharpened up a little bit,” Carville said. “I still think their economic message has got a ways to go.”

There is an upside to rolling out different issues every few weeks: The president has been able to stay in the news while the GOP battles otherwise could have dominated the media.

Bill Clinton became known for rolling out issue after issue. But in Clinton’s case, Newman said, all were tied more successfully to an overarching theme.

“Those were the tentacles that connected back to the octopus,” he said, adding that Obama needs a better octopus. “That’s what they’re looking for. The slogan is the vision statement, it’s critical because everything has to connect with people. It has to have emotion connected to it, in just a few words.”

Obama has never been one to welcome the condensing of his message or worth into an easily digestible, 140-character bumper-sticker slogan. Obama didn’t initially like 2008’s “Change we can believe in,” created by David Axelrod and hailed by Plouffe as a “signature piece of our campaign.”

“I’m not sold on this slogan you guys have cooked up. ‘Change we can believe in.’ Do you really think it says enough? Nothing about issues at all,” he told Plouffe in a phone call, according to Plouffe’s recounting of the 2008 race in “The Audacity to Win.”

But it worked, and on several levels: Aside from the obvious meanings — that he represented a change in Washington and a change in race from previous presidents — it also represented his life story of change from growing up as the child of an often-absent single mother to attending Harvard and becoming a U.S. senator. And, as Plouffe pointed out, it also served as an implicit contrast with Hillary Clinton, whom some in the Democratic base worried would make politically expedient changes in her position if in office — and who cycled unsuccessfully through several slogans.

The Obama camp’s the-other-guy-is-worse focus this time around is reminiscent of the Democrats’ don’t-give-them-back-the-keys type of messages ahead of the trampling they received from the GOP in the 2010 midterms.

But Democratic messaging veteran Mo Elleithee, who worked on Hillary Clinton’s campaign in 2008, said he believes it will work in the presidential election.

“Now we have something to actually judge it against,” he said, noting that the GOP will have been in charge of the House for two years and has a record with which to contrast. Elleithee, who is now working on Tim Kaine’s Virginia Senate bid, said that will work in Obama’s favor against an opponent like Mitt Romney because Romney can be tied to the House GOP.

“He’s wrapped his arms around the House GOP agenda and Paul Ryan,” Elleithee said.

A contrast message has worked before — that was how George W. Bush ran against Sen. John Kerry. But Bush succeeded in part because he was popular at the time on the front America cared about: national security.

Republicans, meanwhile, are relishing the president’s stutter-step messaging. Brendan Buck, spokesman for House Speaker John Boehner, notes that Obama has repeatedly been thrown off message, adding to the mix.

“You can count on two things from the White House right now: a defensive message and an angry tone,” Buck said. “Whether it’s gas prices, Keystone, attacks on the Supreme Court or messages transmitted to Vladimir, the White House has taken its megaphone and turned it into a ‘Kick Me’ sign.”

“The one image, the one idea, which motivates, they haven’t found it yet,” Goldman said.

Goldman pointed to “The Responsive Chord,” a term coined by renowned political messaging guru Tony Schwartz, who created the infamous daisy ad for Lyndon Johnson’s 1964 election campaign that hit on fears Republican nominee Barry Goldwater’s positions would lead to nuclear war.

“During a campaign, you want one big idea,” he said.

But coming up with a slogan is always harder to do from inside the White House than outside.

“It’s a lot harder to do it as an incumbent,” Goldman said, “to come up with a single idea that cuts across every single line of every demographic that you need to be supportive of you.”