"Entrepreneurs and business people around the world and here at home think that at some point America is going to become like Greece or like Spain or Italy, or like California - just kidding about that one, in some ways," he added, to laughter from his audience in Iowa.
The remark seemed likely to bruise egos in a state wrestling with the prospect of tax increases and painful budget cuts. But Romney may have little to lose there - polls show Obama with a comfortable lead in California, where Democrats control the governorship and the Statehouse.
A spokesman for California Gov. Jerry Brown, a Democrat, disputed Romney's assessment. Gil Duran said the state's credit outlook has improved under Brown and that borrowing costs, a major issue facing Italy and other financially struggling European nations, have dropped by hundreds of millions of dollars.
"This is just a paper-thin Republican talking point that doesn't really stand up to scrutiny" Duran said. "He should get some better speechwriters who actually know what they're talking about."
Romney is focused on Iowa's six electoral votes in a state race that both parties think could be close. He told Iowans that Americans have to show investors worldwide they are serious about reining in the nation's spending and debt.
"If they think we are going to get to a point of massive deficits and the potential for economic challenge, why, they're going to have a tough time investing in America," he said.
As Romney and his Republican allies denounced Obama as too far left to be re-elected, they held up an unlikely presidential role model - Democrat Bill Clinton.
Obama is "the anti-Clinton," declared former House Speaker Newt Gingrich, bolstering a line of attack taken up by Romney in speeches and a TV ad as part of a hard sell to working-class voters.
Obama also was pitching to those voters Wednesday, and reaching out to women, whose support is essential to his prospects in November. The president was bound for Colorado to promote wind energy and appear with college student Sandra Fluke, whose congressional testimony became a flashpoint for arguments over contraception, abortion and women's health care.
At a morning rally in Iowa, Romney repeated his charge that Obama is stripping work requirements from welfare and instituting changes to "make America more of a nation of government dependency."
Obama's campaign says Romney is misrepresenting a change that simply gives more freedom to states that requested it to help deal with paperwork. But Gingrich, whose own bid for the GOP nomination was quashed by Romney, argued that the administration's willingness to weigh state requests for waivers amounts to a back-door maneuver to undermine the 1996 law signed by Clinton.
"Clinton was trying to move the party to the center," Gingrich told reporters, referring to the Democratic Party. "Obama is trying to move it to the left."
The former president himself weighed in. Clinton said in a statement Tuesday that the assertion in Romney's ad was "not true."
The effort to cleave Obama from a popular policy of Clinton's presidency comes just weeks before the former president is scheduled to appear as a crowd-rousing, marquee speaker at the Democratic National Convention. Gingrich - who pushed through the 1996 welfare bill and later led the charge to impeach Clinton - said he wanted to remind Americans "how much weaker and less effective a president Obama is than the man who is nominating him."
The welfare issue as pushed by the Romney campaign appeared to be aimed at blue-collar whites in a weak economy and suggested that Obama might be gaining ground politically with his position on taxes.
After the Des Moines rally, Romney was headed to New Jersey to raise more money for his already sizable campaign accounts. On his way to the airport, the former Massachusetts governor stopped to visit a corn field and talk with a farmer about the severe drought gripping much of the nation.
Obama was heading westward to Colorado to make his case to working-class voters and women on Wednesday.
Obama plans to spend three days in Iowa next week, a signal that his advisers see the Midwestern state as fertile soil for his political message, especially his support for wind energy. Wind turbines dot the Iowa horizon and employ thousands of voters. Romney often mocks Obama's support for so-called green energy projects, a position that puts him at odds with Republican leaders in the state.
Obama is launching a two-day, four-city swing through Colorado on Wednesday. His events are expected to focus on the economy, including his call for Congress to extend tax cuts for families making less than $250,000 a year while letting the cuts for higher-income earners expire.
A new Quinnipiac University poll shows Obama and Romney tied among voters in Colorado households earning between $30,000 and $50,000 per year - an important target. Obama leads among voters with lower incomes; Romney is favored by those making more.
Obama planned to emphasize women's health issues at his first event in Denver. The president was to be introduced by Fluke, the Georgetown University student who gained notoriety after conservative talk-show host Rush Limbaugh called her a slut because she supports the Obama health care law's requirement that insurance companies cover contraception.
In an online opinion piece Wednesday, Fluke cited Romney's "dangerous promises" to roll back Obama's health care law. She also noted that Romney hadn't denounced Limbaugh's name-calling.
"If Mr. Romney can't stand up to the extreme voices in his own party, we know he'll never stand up for women and protect the rights that generations of women fought so hard to ensure," Fluke wrote for The Huffington Post.
The president has been running television advertisements in Colorado highlighting his health care overhaul's benefits for women and warning that those benefits could be taken away if Romney wins. On Wednesday the campaign released a video in which actress Elizabeth Banks describes her personal experience with Planned Parenthood and criticizes Romney for promising to eliminate its federal funding.
Both Obama and Romney see women - particularly suburban women from their 30s to their 50s - as crucial to the tight contest in Colorado.
(Copyright 2012 by The Associated Press. All Rights Reserved.)