"I'm for Mitt Romney," the former president said Tuesday in Washington as the doors of his elevator shut, perhaps his only public statement on the race before the Nov. 6 election.
Romney's campaign doesn't foresee the 43rd president playing a substantive role in the race. Aides are carefully weighing how much the former president should be involved in the GOP convention -- and for good reason. The Bush fatigue that was a drag on GOP nominee John McCain four years ago, and on the country, still lingers, including among Republicans.
"The Iraq war? The economy? Let's not revisit President Bush's record," Richard Rinaldi, a 72-year-old Republican, said at a Romney rally last week in Charlotte. "There's no desire to see him campaigning."
Standing nearby, Roger Burba, a 73-year-old Republican from Pineville, N.C., put it this way: "He's back in Texas, where he should be."
While Bush's standing has improved since he left office in January 2009, he remains a polarizing political figure. Romney's aides fear Bush's status could hurt the new Republican standard-bearer in battleground states like Ohio, Michigan and Wisconsin even though Bush could energize the party faithful -- and help raise money -- in solid Republican parts of the country.
There's another risk: Romney linking himself too closely to the former president in any way would give Democrats ammunition to boost President Barack Obama's argument that his Republican rival would restore Bush-era policies.
Bush is said to be enjoying retirement at home in Dallas. He's largely stayed out of sight and out of politics since leaving office and is likely to sit much of the campaign, too. He spends his time raising money for and promoting his presidential library at Southern Methodist University -- the reason he was in Washington on Tuesday when ABC News caught him and elicited the unscripted endorsement. He also gives speeches for charitable causes.
"He's been a very private person. I don't know why that would change," said Republican strategist Danny Diaz, a veteran of Bush's team.
Romney's aides won't speak for the record about the campaign's plans -- if there are any -- for Bush. Bush's office did not respond to a message seeking comment about the campaign or the convention.
Behind the scenes, Republicans close to Romney's campaign say there are no plans to use Bush in a significant way and that the signal from Romney's Boston headquarters -- it's loaded with veterans of Bush's two successful campaigns -- is that any role for Bush would be minimal at best. The Republicans, who insisted on anonymity to discuss strategy, said Romney's team will determine, if it hasn't already, how best to recognize Bush at the party's national convention in August in Florida, where Bush's brother, Jeb, was governor.
Romney's advisers are studying exit polls from the 2008 presidential election, when nearly three-fourths of voters, or 71 percent, said they disapproved of Bush's job performance. Twenty-seven percent approved. Voters were evenly split -- 48 percent apiece -- on whether McCain would continue Bush's policies or take the country in a different direction. Democrats' central criticism of McCain was that his presidency would have amounted to a third Bush term.
Of those who said McCain would continue Bush's policies, just 8 percent voted for McCain; 90 percent supported Obama. McCain carried a substantial majority of those who approved of Bush's performance. But of the 51 percent who strongly disapproved of Bush's performance, McCain won just 16 percent.
Bush's standing is not nearly as dreary any more, but the numbers still show little incentive for Romney to wrap himself in Bush.
A March poll by Bloomberg found that 45 percent of adults had a favorable opinion of Bush, to 50 percent unfavorable. That was better than a January 2009 Pew Research Center poll, taken as Bush was leaving office, that found that 37 percent had a favorable opinion of him, to 60 percent unfavorable.
That's not to say Romney completely ignores Bush, either. On the March day when he was endorsed by Jeb Bush, Romney credited the former president with averting another Depression in 2008. Bush's father, George H.W. Bush, endorsed Romney little more than a week later.
"I keep hearing the president say that he's responsible for keeping America from going into a Great Depression," Romney said of Obama. "No, no, no. That was President George W. Bush and (Treasury Secretary) Hank Paulson that stepped in and kept that from happening."
There are no rules for using former presidents in political campaigns, nor are potential successors bound to embrace them.
But Obama is keeping his Democratic predecessor closer this time around.
Democrat Bill Clinton had a muted role in the 2008 general election after the nasty primary fight between his wife, Hillary Rodham Clinton, and Obama. But Obama has signaled this year that he intends to fully embrace the popular former president -- and take advantage of his political strengths. A prolific fundraiser, Clinton recently appeared with Obama at a money event near Washington. He also has a prominent role in Obama campaign videos.
Clinton was sidelined while still in office in 2000 when Vice President Al Gore kept him at bay after the Monica Lewinsky scandal.
History doesn't offer much precedent for handling former presidents at party conventions, either.
Clinton and Jimmy Carter gave speeches on the first day of the 2004 Democratic convention. In 2000, the elder Bush and Gerald Ford were present when George W. Bush was nominated, but neither man spoke. In 1996, both Ford and George H.W. Bush spoke.
Four years ago, McCain kept Bush at a distance after an awkward joint appearance in the White House Rose Garden. McCain had challenged Bush for the nomination in 2000 and didn't endorse him after Bush prevailed.
During his convention speech in 2008, McCain spoke the Bush name only once -- in reference to Laura Bush.