If the Nevada Democratic Debate was marked by a distinct lack of fireworks, the first half hour of the South Carolina Debate has been a Fourth of July Spectacular.

Obama was itching for a fight from the jump, jabbing Hillary over NAFTA and economic stimulus in the first 15 minutes before firing the big guns — accusing both Sen Clinton and President Clinton of lying about his Iraq record and twisting his line about admiring Ronald Reagan to attack him.

When Clinton said she disagreed with the Republican ideas Obama seemed to be praising, Obama took exception. After a brief shouting match, Obama lashed out — telling Hillary that while he was fighting those Republican ideas as a community organizer in Chicago, “you were a corporate lawyer sitting on the board at Wal-Mart.”

Clinton fired back with a low blow of her own, saying “I was fighting against those ideas when you were practicing law and representing your contributor, Rezko” — the indicted Chicago slum-lord who was one of Obama’s biggest political benefactors.

Meanwhile, poor John Edwards was left asking Wolf whether there were just two people at the debate. Unfortunately for him, the answer is only two with a chance of winning the nomination. But he’s having an excellent debate playing the spoiler, needling Clinton and (mostly) Obama — and often coming off like the one grown-up at the kiddie table.

There’s more to come… as Senator Clinton said, “we’re just getting warmed up.”