TILTON, N.H. (AP) -- It's an opening salvo of the presidential campaign, minus actual presidential nominees.
Vice President Joe Biden unleashed a biting critique of Mitt Romney's policies Friday and the Republican came swiftly back at him -- a full-contact preview of what the general election might look like should Romney win the GOP nomination to challenge President Barack Obama.
All this, before a vote is cast in the Republican race, The Iowa caucuses, looming Jan. 3, are the first step in the voting to pick a Republican nominee.
In an opinion piece published in The Des Moines Register, Biden portrayed the Republican frontrunner as the purveyor of failed, retreaded economic ideas. Romney shot back that Biden and Obama live an economic "fantasyland" out of touch with the real world.
Biden's jabs mark a major escalation in Obama's re-election campaign and refocus his political team on Romney, the former Massachusetts governor whom Obama advisers have long considered his most likely opponent. And it switches Obama away from his just-concluded tax cut victory over House Republicans to the GOP presidential field just 12 days before the Iowa caucuses.
"Romney appears satisfied to settle for an economy in which fewer people succeed, while the majority of Americans are left to tread water or fall behind," Biden wrote.
The Obama team may be betting on Romney, but his Republican rivals were conceding no such ground.
Campaigning in South Carolina, former House Speaker Newt Gingrich derided Romney as a "Massachusetts moderate trying to come down and pretend to be a conservative. But I'm not going to say anything stronger than that. I'm going to focus on positive things."
Asked later how that wasn't being negative, Gingrich said: "I didn't criticize him. I described him accurately."
And he swiped at rival Ron Paul for wanting to shut overseas military bases, a stark departure from the Republican mainstream and one not bound to sit well in pro-military South Carolina. "The only person I know who is for a weaker military than Barack Obama is Ron Paul," Gingrich told 300 people outside a Columbia restaurant. "If we become isolationist, the world would become a more dangerous place overnight."
Rep. Michele Bachmann's campaign said Friday she would start radio and TV commercials in Iowa, her first since her straw poll victory in the state in August. In them, she stresses her Christian values and that she's "an Iowa girl from Waterloo."
Biden's words, meanwhile, summed up a running story line about Romney that Obama's campaign and the Democratic Party have been refining for months. The piece also was a direct rebuttal to Romney's recent claim he wants "an opportunity society" versus what he called Obama's "entitlement society."
Biden reiterated a major theme of Obama's re-election effort, one the president spelled out in a recent speech in Kansas where he declared that the middle class was at a make-or-break moment. In taking on Romney, Biden defined "opportunity" in his own terms.
"We believe deeply in opportunity -- that if you work hard and play by the rules, no opportunity should be out of reach," he wrote. "This is a fundamentally different vision than what the other side has proposed."
Romney, speaking at the Tilt'n Diner, quickly countered that it was Obama who is hurting the country and expressed astonishment that Biden would have the "chutzpah ... the delusion" to write such a piece.
"This president and his policies have made it harder on the American people and on the middle class," he said. "And I don't think they get it. I don't think they understand from fantasyland what's happening in real America. They need to get out to diners like this."
The timing, placement and direct response to Romney represented a remarkable early volley from the Obama camp, using the most potent voice next to the president himself to set a new signpost on the re-election season. And it signaled an aggressive strategy to challenge his GOP opposition and engage even though the Republican nomination could remain unsettled for months.
In the opinion piece, Biden said Romney's proposals for the economy "would actually double down on the policies that caused the greatest economic calamity since the Great Depression and accelerated a decades-long assault on the middle class."
"Romney also misleadingly suggests that the president and I are creating an 'Entitlement Society,' whereby government provides everything for its people without regard to merit, as opposed to what he calls an Opportunity Society,' where everything is merit-based and every man is left to fend for himself," Biden wrote.
In essentially placing its bets on Romney, the Obama camp elevated his stature in the race, particularly in Iowa where he is running neck-and-neck with Gingrich and Texas congressman Ron Paul.
Romney was clearly ready -- and eager -- to engage with the White House. While he generally has to be asked, or even pressed, to criticize Gingrich, he hit back at Biden at the first opportunity.
"I think they realize what's coming," he said. "I hope they're right. I hope I'm the nominee."
Romney aides said campaign days like this help him against his GOP rivals, positioning him as the candidate best able to take on Obama in the fall and addressing a top Republican goal: selecting a nominee who is electable against the president.
The Obama campaign also chose Iowa to deliver the Biden message because it is an epicenter of national politics and where it was sure to get intense attention.
Moreover, Iowa is a general election swing state that Democrat Al Gore won in 2000 but President George W. Bush won in 2004. Obama beat Republican John McCain in the state in 2008 by 8 percentage points. Biden's message clearly aimed for the state's general election voters as well.
Earlier this week, Romney accused Obama of deepening the economic crisis and backing policies that would redistribute wealth instead of creating equal opportunity for people to do well.
Romney said his policies would turn the U.S. into an "opportunity society" while Obama's vision for an "entitlement society" would make more people dependent on government welfare.
"The only entitlement we believe in is an America where if you work hard, you can get ahead," Biden wrote in the op-ed.
Biden's piece hinted at another line of attack on Romney -- that the former governor is a man of wealth and privilege. Biden, in his piece, stressed his own family's working class roots and how his father's pride was "put to the test when he found himself struggling to make ends meet."
Romney, by contrast, is the son of former American Motors Corp. chairman and Michigan Gov. George Romney. Romney also made his own fortune as a venture capitalist, a point Obama's Democratic surrogates have used to portray Romney as out of touch and elitist.
Hunt reported from New Hampshire; Kuhnhenn reported from Washington. AP White House Correspondent Ben Feller and Associated Press writers Will Lester, Brian Bakst, Seanna Adcox and Shannon McCaffrey contributed to this report.