DENVER—When President Barack Obama and Mitt Romney meet for their first debate on Wednesday, there will be handshakes and smiles—and maybe even a good-natured pat on the back or two.
But they probably won't be genuine. The moment will likely mark a brief moment of civility between two fiercely competitive candidates in an election that has been defined by increasingly personal attacks.
Not unlike presidential contenders before them, Romney and Obama will take the stage while likely still harboring hard feelings over the blistering attacks their campaigns have traded in recent months.
The low blows still fresh in Romney's mind: An assault on his record as chairman of Bain Capital, including charges from a senior Obama campaign aide that he may have committed a felony in not being forthcoming about when he left the company. Then there's the ad from a super PAC run by former Obama aides that implied Romney might be responsible for the death of a wife of a steelworker who was laid off from a Bain-owned company.
On the flip side, Obama has been stung by Romney's refusal to reject supporters like Donald Trump, who continues to question whether the president was really born in the United States. More recently, the president and his team fumed over Romney's claim that Obama had sympathized with those responsible for the deadly attacks on American diplomatic missions overseas, which resulted in the deaths of four U.S. citizens.
The back-and-forth has soured what was already a cool relationship between Obama and his GOP challenger. The two have met only a handful of times over the years. As the candidates face off as debate opponents for the first time, a major unknown is whether that built-up anger over the negative attacks will show itself onstage.
"Each has been coached to restrain that emotion, but it is undeniably there," a friend of Romney's, who declined to be named talking about the candidate, told Yahoo News.
Aides to both Romney and Obama have downplayed the level of personal animosity between the two candidates—insisting it is, as one Obama aide put it, "overstated."
"It's not about hating him. He, of course, doesn't," the Obama aide, who declined to be named discussing the president's personal views, told Yahoo News. Rather, the staffer insisted, the president is simply "incredulous" about Romney's policies and the effect they would have on the country.
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The Romney camp offered a similar explanation, pointing out that the Republican nominee's criticism of the president "isn't personal," as one senior adviser put it. "He just doesn't think Obama should be president of the United States," the Romney aide said.
But the "nothing personal" argument seems hard to believe, especially since the candidates have enthusiastically embraced their roles as attack dogs on the trail, delivering withering critiques of their opponents. That outspoken position is usually left to the surrogates out of fear that the actual candidate could alienate middle-of-the-road voters by spewing nasty attacks.
For months, Romney tempered his criticism of Obama by telling crowds that he believed the president was "a nice guy" who simply didn't understand how to turn the economy around. But as the Obama campaign went after Romney on Bain and his personal wealth, the GOP candidate dropped that line, embracing a tougher stump speech critical of his Democratic rival.
"He demonizes some. He panders to others. His campaign strategy is to smash America apart and then cobble together 51 percent of the pieces. If an American president wins that way, we all lose," Romney said of Obama in August. "So, Mr. President, take your campaign of division and anger and hate back to Chicago, and let us get about rebuilding and reuniting America."
Romney's speech came just hours after Obama made a joke on the stump about Romney's dog, Seamus, who was famously strapped atop the family car during a vacation years ago. A few days later, Romney struck back again, making a birth certificate joke many interpreted to be about Obama even as his campaign denied it.
Romney has complained about negativity in the race, pointing to a phone call he received from Obama in May after he officially clinched the GOP nomination. He said the president told him he wanted to have a "meaningful debate," not a race dominated by personal attacks.
"I'm still waiting for that to happen," Romney told Fox News in July, a hint of bitterness in his voice.
Even as his campaign insists Romney doesn't hold a grudge against Obama, the GOP nominee has spent weeks in debate prep working to make sure he doesn't lose his temper or get irritated with Obama—a testiness that often showed through during GOP primary debates with rivals Rick Perry and Newt Gingrich.
According to one Romney aide, Ohio Sen. Rob Portman, who is portraying Obama in Romney's mock debates, was instructed to push Romney's buttons in hopes of making the candidate angry—all to teach him how to keep his cool during the real debates. It's a tactic that has apparently worked, which Romney recently acknowledged during a rally in Portman's home state.
"He plays Barack Obama; he plays him well, too," Romney told supporters at a rally in Dayton, Ohio. "After the, you know, hour and a half or so is over, I'm like, I want to kick him out of the room he's so good."
When Obama and Romney walk onto the debate stage on Wednesday night, they will do so almost as strangers. According to aides, the two have met fewer than five times. Their first meeting occurred in late 2004, when they both participated in an annual dinner sponsored by Washington's Gridiron Club. Obama had just been elected as the new senator from Illinois, while Romney was midway through his one term as governor of Massachusetts.
"We had fun doing that together. He's got a lovely wife. My wife thinks she's just terrific," Romney said of his future rival in an interview with NBC host Jay Leno in 2008.
The two later crossed paths during the 2008 campaign, running into each other while campaigning in New Hampshire and later at a presidential debate sponsored by ABC News.
When Romney's wife, Ann, was diagnosed with breast cancer in late 2008, Obama, then the president-elect, phoned his future GOP rival to offer his support.
"He was kind enough to call our home when my wife was ill, and he said that he and Michelle had my wife in their prayers," Romney told CNN in a January 2009 interview. "And I said, 'Mr. President-elect, Ann and I have you in our prayers."
Asked about Romney in an interview with the Associated Press in August, Obama offered some kind words about his GOP rival.
"I don't really know him well," Obama told AP. "I think Gov. Romney obviously has achieved extraordinary success with his businesses, and he's obviously very focused on achieving the presidency. He cares deeply about his family, and I think he cares deeply about his faith."
While Romney and Obama emphasize their differences on the trail, the truth is they have more in common than one might think. Among other things, both are graduates of Harvard Law School and both are known to be intensely competitive. The two have both been criticized for keeping their distance from members of the political establishment, preferring instead to spend time with family and a small circle of loyal friends.
Romney's political rivals have described him as "cool" and lacking emotion—a critique that has been lobbed at Obama more than a few times.
And there's one more thing the two have in common heading into Wednesday's debate: a staunch belief that the other should not be president.