By Steve Holland
WASHINGTON (Reuters) - If Rick Perry is going to win the 2012 Republican presidential nomination, he'll have to do it based on something other than his debate performances.
The Texas governor fought his way through another two-hour session as his top rivals, Mitt Romney and Herman Cain, coasted through relatively unscathed, scoring points, defending their plans.
Perry avoided major stumbles that afflicted him at three previous debates, but he did not take advantage of opportunities to land punches on Romney. He specifically did not carry out a sustained assault on the healthcare plan that Romney developed as governor of Massachusetts.
Perry, popular with social conservatives looking for a Romney alternative, cannot be written off. His $17 million raised in the third quarter of this year was a powerful testament to his ability to fully fund a campaign in the early voting states.
But he may have missed an opportunity to claw back some ground lost to Romney in national polls of Republican voters, after bursting onto the scene in first place in August only to fall behind former Massachusetts Governor Romney and businessman Cain.
"I thought he was rather cautious and I think because of that he was treated as somewhat of an afterthought," said Andy Smith, director of the University of New Hampshire Survey Center.
The stage was set for a big Perry attack on Romney when NBC News reported earlier in the day that Romney healthcare advisers had met with President Barack Obama's healthcare team during the time that Obama was developing the overhaul that conservatives want to repeal.
Given the chance to address Romney on the topic, Perry asked about rising insurance premiums for small businesses in Massachusetts as a result of "Romneycare."
It was a fair question, but it gave Romney an opportunity to defend his plan and accuse Perry of running a state with a large number of uninsured children.
"I'm proud of what we are able to accomplish," Romney told Perry. "I'll tell you this, though. We have the lowest number of kids as a percentage uninsured of any state in America. You have the highest."
Republican strategist Matt Mackowiak said Perry's debate was better than his previous sessions but that he missed some opportunities, especially on healthcare.
"Ultimately Perry didn't go for the jugular, and I don't understand why. He had a huge opportunity to do so," said Mackowiak.
And perhaps worst of all, Perry came to a debate about the U.S. economy without bringing a specific plan to trigger economic growth and create jobs, saying instead he would unveil his proposals over the next three days.
Asked to name some specifics, Perry stressed the need to increase domestic U.S. energy production: "Well, clearly, opening up a lot of the areas of our domestic energy area. That's the real key."
New Hampshire Republicans, who will have a big say in who becomes the nominee when they hold the country's first primary in mid-January, will have to wait to hear the details of his plan.
"It strikes me that if you're going to go to a major debate after you've gotten your butt kicked in the previous debates, and you it's about the economy and jobs, to stand up there and not give any specifics is not helpful," said Steve Duprey, a New Hampshire Republican who advised Senator John McCain's 2008 presidential campaign.
(Editing by Sandra Maler)