AURORA, Colo. — As he tries to persuade Republicans that he can jump-start the nation’s beleaguered job market, Mitt Romney is sharpening his attack on last year’s overhaul of financial industry regulations.

The GOP presidential front-runner continues to deliver his now-familiar assault on President Obama’s economic record. But the 2010 Dodd-Frank bill that tightened federal regulations on Wall Street has emerged as a key element of Romney’s evolving stump speech.

In a short address to more than 250 supporters at a restaurant in this Denver suburb on Monday, and again in a roundtable talk that followed with a dozen small business owners, Romney said the Democratic-led overhaul has created “uncertainty” that paralyzes Main Street.

“Banks are afraid to make loans right now because of the government hanging over them like gargoyles,” Romney, a former Massachusetts governor and business executive, said during the roundtable discussion.

Romney said small business owners cannot acquire capital because banks won’t give loans since they are under “extraordinary pressure and scrutiny” from federal regulators.

“Almost everything the president did had the opposite effect of what was intended,” Romney said. “He said, okay, we’re not going to re-regulate the banking sector. Well, what he caused was the banking sector to pull back, and that’s the very sector that’s got to step forward to help get the economy on its feet again.”

As he worked the tables at Brewery Bar, a Mexican joint in an Aurora strip mall, Romney was loose and appeared at ease, posing for pictures, signing baseball hats and dipping into a bowl of guacamole.

At one table, a boy offered Romney a $1 bill that he had folded origami-style for good luck. The candidate happily accepted it, but then rifled through his wallet looking for money to give the boy in return. Romney had a $100 bill, but evidently did not want to give that away. An aide handed him a $1 bill, but Romney said that wasn’t enough.

Then, deep inside his leather billfold, Romney found a $5 bill. “We’ll give you an Abraham Lincoln back,” he said, handing it to the boy.

The centerpiece of the pitch Romney has made to voters from New Hampshire to Florida to Colorado is that he, not Obama, has the private sector experience necessary to spur job growth.

“I look at this and say, you know, we’ve got a nice group of folks in Washington,” Romney said. “They just don’t have experience in the private sector. They don’t know what it takes to create jobs. And I spent my life doing that.”

Asked later by a reporter to name a single economic policy of Obama’s that he thinks has worked, Romney came up short.

“Of his $787 billion stimulus plan, there may have been something in there that was good, but overall what his stimulus did was to protect people in government jobs rather than create incentives for the private sector to hire,” Romney said. “It just has been a failed economic policy from start to finish and that’s why we have, three years in, people wondering, where’s the beef?”

Romney also said he expects more candidates to enter the 2012 presidential race. “The competition on the Republican side, you’ve seen them on the stage and my guess is we’ll have at least one or two more, maybe more than one or two more,” Romney told reporters.

Former Utah governor Jon Huntsman Jr. is planning to officially launch his campaign Tuesday in New Jersey, while Texas Gov. Rick Perry is weighing a run.

Romney called the field “a great group,” adding that “we don’t agree on all the issues, but we probably agree on 70 or 80 percent.”

Democrats, meanwhile, welcomed Romney to Colorado by charging that when he was governor, Massachusetts ranked 47th in the nation in job creation. Rick Palacio, chairman of the Colorado Democratic Party, said Romney’s policies would be a “harsh blow to middle-class Coloradans.”

Romney’s visit to Colorado — not one of the earliest primary states, but a critical general election battleground — coincided with his campaign swing through Western states, where he is raising money and picking up the endorsements of key Republicans. He and Huntsman both will visit Utah this week to seek money from the Mormon community, where they each have deep roots.

In Colorado, Romney won the endorsements of Attorney General John W. Suthers as well as former senators Hank Brown and Wayne Allard, former governor Bill Owens and former representative Bob Beauprez.

Earlier on Monday, Romney was in Idaho, where he named Gov. Butch Otter and Sen. Jim Risch as co-chairmen of his state steering committee.