John Edwards lands "heavy hitter" in Greg Craig

The latest addition to former Sen. John Edwards' legal team is a "pretty heavy hitter" with a long resume of high profile cases and bosses.

Greg Craig, who represented both Presidents Clinton and Obama, is the newest member of Edwards' team as the former presidential candidate hopes to avoid indictment for violating campaign finance laws.

In fact, CBS News has learned that while the hiring of Craig has just recently become public, he was actually brought on six weeks ago, reports CBS News chief legal correspondent Jan Crawford. He left his post as President Obama's counsel in January 2010.

News of Craig's addition comes as speculation grows that a federal grand jury is wrapping up its investigation into whether Edwards improperly used campaign funds to hide his mistress, Rielle Hunter.

The presence of Craig, who also served as one of President Clinton's lawyer during the Monica Lewinsky scandal, has some experts speculating that Edwards is worried about where this investigation is heading.

"That's one of the reasons Mr. Craig has been brought in -- to assist in that effort to avoid indictment on the front end," Kieran Shanahan, a former federal prosecutor, told CBS News.

But sources close to the case tell CBS News that an indictment is not imminent. And Craig's experience may prove a valuable addition for Edwards.

"I have seen Greg Craig in lot of different cases over the years and they all have one thing in common - he takes clients he believes in, cases he thinks he can win. He is very cautious and savvy. He's just not someone who's going to fight ... one of these uphill battles. So I would say ... that is a pretty good sign for John Edwards," Crawford said on "The Early Show" Friday.

"In many ways, oddly enough, this could b one of Greg Craig's lower-profile cases," Crawford continued. "He represented Elian Gonzalez and helped get that boy back to cuba. He was involved in [attempted Reagan assassin] John Hinckley's defense and more recently in the high-profile defense of Goldman Sachs. So [he's] a pretty heavy hitter here to say the least."

Edwards began his affair with Hunter during his presidential run in the 2008 campaign. The two had a daughter together. Two years later, Edwards' marriage to his wife Elizabeth crumbled. She died in December after a lengthy battle with breast cancer.

But a tarnished image could be the least of Edwards' problems. If he's indicted he could face a federal prison sentence.