Obama "basically adopted a lot of thoughts that we've had on the campaign trail," Romney told NBC News. "Unfortunately, what he says and what he has done are so dramatically different that you have to be a little surprised."
Obama offered a populist economic vision Tuesday night, pledging to use government power to balance the scale between America's rich and the rest of the public.
His proposals included limiting tax deductions for companies that move jobs overseas and rewarding companies that return jobs to the United States. He said a major part of his agenda would be to expand domestic energy supplies, from oil and natural gas to wind and the sun. He also proposed a new trade unit to investigate unfair practices in countries including China.
"Well, in some respects, I have to compliment the president on adopting a whole series of ideas that I've been speaking about for the last several years," Romney told NBC.
"If you want to get the economy going, lower corporate tax rates -- of course, he's raised them. Lower the level of regulation -- of course, he's added regulation at three times the rate of his predecessor. Take advantage of all of our energy resources. He's really held off on coal, on oil, on gas, on nuclear. Then, he said crack down on China.
"Those are the things I've been saying," Romney said. "Unfortunately, what he's been doing is the exact opposite of that, and that's one of the reasons it's been so hard for this economy to recover."
Gingrich said Obama was concerned only about staying in power and keeping money out of the hands of people who Gingrich said were responsible for jump-starting the U.S. economy.
"For the president and a large part of the political class, it's about their power, their right to rule," Gingrich said in a statement after Obama's address.
"They just want to take money from Joe the Plumber -- the small-business people who makes over 90 percent of the new jobs -- and redistribute it to the government bureaucracy and their political friends and allies," he said.
"To create jobs and growth in this country, we must start with dramatic tax reform that lowers taxes and maximizes capital investment and job creation," Gingrich's statement said.
"We must return to a dollar as good as gold whose purchasing power is the same in 30 years as it is today," he said. "We must dramatically expand American energy production. We must have smarter regulation at the same time we abolish destructive and costly regulatory systems. ... And finally, unlike the current administration, we must have faith in job creators."
Gingrich, who is leading Romney in the Florida GOP polls after beating him in the South Carolina primary, said separately he would deliver "a visionary speech" Wednesday "on the United States going back into space in the John F. Kennedy tradition."
It will be one of a series of speeches on "big solutions for a big country" before Tuesday's Florida primary, Gingrich told C-SPAN.
The other speeches will be on healthcare, housing, the economy, Cuba and Latin America, he said.
About 452,000 Florida Hispanics are registered Republicans, the Pew Hispanic Center says. About 565,000 are registered Democrats.
Rep. Ron Paul of Texas, third in the Florida polls, said in a statement Obama "claims to want an economy where everyone gets a fair shot, everyone does their fair share and everyone plays by the same set of rules. Yet he remains committed to the same old system of debt, deficits, bailouts, and cronyism that created our economic problems."
The federal debt and deficit require "immediate measures," Paul said, "like the $1 trillion in spending cuts that would take place in my first year as president under my Plan to Restore America."
Former U.S. Sen. Rick Santorum of Pennsylvania said Obama's speech was filled "from beginning to end" with "empty promises and grand platitudes that will do nothing to help the millions of Americans who are unemployed or underemployed find a good-paying job."
"Rather than call for decisive action in allowing projects like the Keystone Pipeline or reducing the regulatory burden his administration has imposed, the president declared war on those who are most successful in our society," Santorum said in a statement.
"Barack Obama should realize he's the president of all Americans, but sadly, he has instead chosen to govern and campaign as the divider in chief," he said.