By Andy Sullivan
Speaking at a meeting of newspaper publishers, Clinton sought to strike a balance between the hawkish approach taken by the Bush administration and her Democratic rival Barack Obama's call for face-to-face talks with the Iranian president.
"The approach that the Bush administration has taken toward Iran has been a loser. It has neither changed behaviors or produced results," said Clinton, a former first lady who would be the first woman president.
"I've advocated both that carrot and that stick, and I think that would be what I (would) take to try to create the beginning of lower levels of diplomatic engagement, some ongoing process," the New York senator said.
The West accuses Iran of trying to acquire nuclear weapons under cover of a civilian program. Iran denies the charge and says it needs nuclear technology to meet electricity demand.
The Bush administration has led international efforts to penalize Iran for failing to allay suspicions over its nuclear work.
The expected Republican nominee for the November election, Arizona Sen. John McCain, speaks aggressively against Iran for its nuclear program and its influence in Iraq.
Obama, Clinton's rival for the Democratic nomination to face McCain, has advocated meeting with Iranian President Mahmoud Ahmadinejad as a way to break the standoff and has accused Clinton of siding with Republicans because of her Senate vote last year to label Iran's Revolutionary Guard a terrorist organization.
Clinton, who has painted Obama as too inexperienced to protect U.S. interests during a crisis, defended her vote.
"I think going after the Revolutionary Guard and labeling them as a terrorist organization actually gives us a stronger hand at the diplomatic table," she said.
Asked if she would initiate covert actions against Iran if she were president, Clinton said: "Without saying anything out of school, I'm sure that there are many covert actions going on."
(Editing by David Wiessler)
(To read more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at http:/blogs.reuters.com/trail08/)