Davenport, Iowa (CNN) - On Monday, the only history professor running for president offered stern lectures on economic policy, against President Obama - and even attempted to school Mitt Romney and Rick Perry.
"I literally felt like, the other night, I was the recess monitor on the playground, watching these two kids," Newt Gingrich said at a town hall in Davenport, Iowa. The former House speaker was referencing the bitter back-and-forth between the former Massachusetts governor and current Texas governor at last week's Republican presidential debate in Las Vegas, sponsored by CNN and the Western Republican Leadership Conference.
Gingrich also warned "that bickering is not going to be the road to the White House," adding, "There's nothing wrong with policy debates...Policy dialogue, handled with civility, is exactly what politics should be."
As if to set an adult example, Gingrich highlighted his own policy ideas while dutifully picking apart those of others. Saddled with stubbornly low poll numbers, Gingrich hopes his message will catch fire with more voters in the key early voting states of Iowa, New Hampshire and South Carolina.
The candidate played up key elements of his recently revealed "21st Century Contract with America." Among the proposals: zero capital gains tax "so we have hundreds of billions of dollars poured into the country to create new jobs and to create new opportunities," 100-percent expensing for new capital equipment purchasing, a 12.5-percent corporate tax rate, and abolishing the so-called "death tax."
"I believe it is fundamentally immoral for a society to say to somebody: 'If you work hard, you save, you're frugal, you do the right things, we have the right to take half of it away from you to give to people who didn't spend their lifetime doing what you did,'" Gingrich said.
The former House speaker also reiterated his proposal for an optional flat tax of 15 percent or less.
During his speech, Gingrich trained most of his fire on obvious political targets: President Obama, Democrats and liberals.
"I've been trying to figure out how to explain in clear language how fundamentally wrong the Left is," the candidate said. "They're wrong about ideology. They're wrong about the nature of America. They're wrong about our foreign enemies. And they're wrong about the economy."
He continued: "And people say to me, 'How quickly could you turn the economy around?' This economy will start to get better late on election night when people realize Obama is defeated."
But the former history professor also laid into his own Republican rivals.
On Ron Paul's debt reduction plan for cutting $1 trillion in the first year of a Paul administration, Gingrich said: "I doubt very much if you can cut $1 trillion in one year." He noted the devastating impact it would have on many agencies across the country. And on Herman Cain, Gingrich said it's right for the conservative businessman to be forced to defend his 9-9-9 economic plan.
Gingrich used his most colorful language for the movement known as Occupy Wall Street.
"Look, I identify with their anger. I just think their solutions are really stupid," Gingrich said.
"The tea party goes out and studies the constitution, studies the Federalist Papers, studies the Declaration of Independence. The folks I've been watching on TV don't study anything. They just use foul language and explain that they're basically anarchists and nihilists. That's what's wrong with the Occupy Wall Street crowd," Gingrich added.
"[Former House Speaker] Sam Rayburn used to say: 'Any jackass can kick down a barn, but it takes a carpenter to build one,'" Gingrich added.
–Follow Shannon Travis on Twitter: @ShanTravisCNN