IRWIN, Pa. – A fiery Mitt Romney on Tuesday accused President Obama of believing the government is more vital to a thriving economy than the nation’s workers and dreamers, scrambling to get back on message by declaring of Obama, “I’m convinced he wants Americans to be ashamed of success.”

The new Romney approach came as Democrats pressed for the release of more of Romney’s tax returns and hounded the Republican candidate over discrepancies in when he left his private equity firm. The conservative magazine National Review urged Romney to release more of his tax records.

Obama has been trying to keep Romney focused on matters other than the sluggish economy, even releasing a single-shot TV ad Tuesday that suggests Romney gamed the system so well that he may not have paid any taxes at all for years.

As the campaign’s tenor grew combative, Romney seized on comments Obama uttered while campaigning in Virginia last week.

The president, making a point about the supportive role government plays in building the nation, said in part: “Somebody helped to create this unbelievable American system that we have that allowed you to thrive. Somebody invested in roads and bridges. If you’ve got a business, you didn’t build that. Somebody else made that happen.”

Obama later added: “The point is, is that when we succeed, we succeed because of our individual initiative, but also because we do things together.”

The challenger pounced.

“To say that Steve Jobs didn’t build Apple, that Henry Ford didn’t build Ford Motors, that Papa John didn’t build Papa John Pizza ... To say something like that, it’s not just foolishness,” Romney said from a campaign rally outside Pittsburgh. “It’s insulting to every entrepreneur, every innovator in America.”

Romney added: “I tell you this. I’m convinced that he wants Americans to be ashamed of success.”

The Obama campaign said Romney had distorted Obama’s message by taking him out of context. Obama’s intended point – one he made again in Texas on Tuesday – was that government plays a role in helping people and businesses succeed by building roads, hiring teachers and firefighters, and looking out for the public good.

“There are some things we do better together,” Obama said in San Antonio at the start of a lucrative fundraising day in Texas. “We rise or fall as one nation. That’s what I believe. That’s what our history tells us. That’s what our future demands. That’s why I’m running for a second term as president of the United States.”

A consistent part of Obama’s “bottom-up” economic message is that individual initiative and hard work should be rewarded. But in a war of words, with both sides eager to jump on any gaffe or inelegant phrase, Romney saw a way to paint Obama as a big-government Democrat.

Romney is trying to shift attention away from his business record and his tax returns with a fresh assault as Obama, anxious about losing his fundraising edge, turned to Republican-tilted Texas to raise millions of dollars from gay, Latino and big-dollar donors.