"There are a lot of different levers that can be pulled to make sure that we create a tax code that's much more growth oriented, that has lower rates, but that also generates the revenue that we need," Romney domestic policy director Oren Cass said.
He would not be more specific other than to cite the Simpson-Bowles Commission, a bipartisan panel that outlined a broad deficit-cutting plan that would wipe away most tax credits and deductions, tax capital gains as ordinary income, and increase federal gasoline taxes, among other things.
Cass was careful not to endorse any of the commission's specific recommendations.
How close is the campaign to having final details?
"I would just say we're in the middle of it," Cass said.
Romney's positions on foreign policy are equally unclear in some cases.
His rhetoric indicates that the world might expect the hawkish foreign policy prescriptions that guided President George W. Bush. But when pressed, Romney's top foreign policy adviser said he agrees with some of Obama's plans.
On Afghanistan, Romney says Obama's 2014 timeline to hand over security responsibility to Afghan forces is "doable," according to foreign policy director Alex Wong.
"That's something (Romney) thinks is operable, but he emphasizes that any time frame must be conditions based," Wong said.
And on Iran, Romney declared, "If we re-elect Barack Obama, Iran will have a nuclear weapon. And if we elect Mitt Romney, if you elect me as the next president, they will not have a nuclear weapon."
Obama has not ruled out an attack, but has not been as threatening as Romney.
"If it's necessary to prevent Iran from obtaining a nuclear capability, Gov. Romney is willing to use military action. That's obviously not the optimal choice, but you have to be willing and you have to communicate your willingness to use the military option and have it be very credible," Wong said, largely echoing Obama's position. "Barack Obama has done a lot to undermine the military option. If you look closely, he says, 'Well it's on the table,' but he's never said he would use it if necessary."
Meanwhile, it's unclear if Romney will amend his strategy in the months leading up to the Nov. 6 general election. Daniels is largely alone among prominent supporters in calling for more transparency.
Cass suggested the campaign may be more forthcoming in some areas.
"I think the governor's already laid out a lot of specifics on policy," he said. "But certainly as you see the campaign progress, we will continue to provide more detail."
Associated Press writers Stephen Ohlemacher and Steven R. Hurst in Washington contributed to this report.
EDITOR'S NOTE _ An occasional look behind the rhetoric of political candidates.
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