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Republican presidential hopeful Mitt Romney greets suporters Saturday after holding a forum at American Legion Post 15 in Sumter, S.C.

SUMTER, SC-- With only a week remaining before polls open in the South Carolina primary, one could be forgiven for confusing tonight's rally with a general election event. Mitt Romney kept his focus squarely on President Barack Obama, delivering fresh attacks, and ignoring altogether his Republican rivals.

"I've watched the president over the last three years and I've been disappointed. He's failed the American people. He likes to say that he has had extensive experience working alongside hardworking Americans. Now you listen to those words carefully," Romney said during a rally at a VFW hall. "He's had experience working alongside hardworking Americans. I think it helps to have actually been a hardworking American, in a hardworking American job."

"I think you're going to find over the coming year that the president is going to be doing a lot of explaining about how it is being a community organizer taught him to run an economy," Romney predicted.

Romney's use of the phrase "alongside hardworking Americans" suggests he was referencing a memo released Friday by an Obama campaign strategist calling into question the validity of Romney's private sector expertise and looking to paint him as a corporate raider.

"Mitt Romney boasts about understanding the 'real economy,' but President Obama has worked alongside hardworking Americans in that 'real economy.' President Obama — who, like Mitt Romney, earned a degree from Harvard and all the opportunities that affords — began his career helping jobless workers in the shadow of a closed-down steel mill. Mitt Romney, on the other hand, made millions closing down steel mills," the memo from Obama deputy campaign manager Stephanie Cutter read in part.

Saturday, the Romney campaign also responded with a memo of its own -- using the same language Romney used Saturday night -- to attempt to drive home the distinctions between Romney's private sector experience and President Obama's.

"The President will have all year to elaborate on how his time as a community organizer helped him understand the implications of tax increases for investment decisions, the impact that overregulation can have on business confidence, and the way that trade policies can support or disadvantage American exporters," the memo from Romney policy director Lanhee Chen said. "He can also describe for voters how his law school lecturing duties showed him the extraordinary economic potential of the nation’s energy resources or the challenges that power-grabbing union bosses pose to businesses and workers."

Warming up the crowd of several hundred at Saturday night's rally, and vowing to help Romney "ride this wave all the way to Saturday," South Carolina Gov. Nikki Haley turned the Obama campaign's focus on Romney into a reason for voters to support him in the Republican primary.

"You know what the icing of the cake is? There are six people in the primary. President Obama is only talking about one," Haley said, gesturing to Romney. "This one, because he's the one he can't beat."