Rielle Hunter is the remaining wild card in the John Edwards trial. Will she or won't she testify? And if she does testify, what might she say? Prosecutors are hoping to conclude their case against the former senator and onetime presidential contender over alleged campaign finance violations by week's end, but it's still unclear whether they will chance having Hunter on the stand. She was, after all, a disruptive presence during Edwards' campaign back in 2008, considered by those close to him to be dangerous for his run for presidency and even, by Edwards himself, a "crazy slut." In the three weeks of the Edwards trial, Bob Woodruff, James Hill, and Beth Lloyd explain in an ABC News piece, "Hunter has been called 'crazy' and a 'loose cannon' who relied on a 'spiritual adviser' for everything from the right dressing for a Reuben sandwich to the best place to have the baby Edwards secretly fathered."

So, will the prosecution actually risk having her on the stand? And what might they gain—or lose—if they do?

Edwards reportedly considered Monday a good day for himself in the trial, in which he's facing 30 years in prison if convicted. A letter Bunny Mellon had dictated to him was excluded as evidence, and Mellon's lawyer Alex Forger testified that Mellon had given Edwards money as a personal gift, not as an explicit campaign donation, because, simply, she liked him. Remember, Edwards is on trial for using campaign donations to hide his affair with Hunter and the fact she was pregnant to the voting public. Presumably, her insights could reveal much about what actually happened. Yet, per ABC News:

"It is dangerous to call her at the end, because if she flops for the government, it's not the note that you want to end on," former prosecutor Kieran Shanahan told ABC News. "At the same time, I just think the story is incomplete without her and she will acknowledge that she did receive the money."

Edwards claims that he never asked Mellon for money personally, and that former aide Andrew Young was after the money for himself, partly to build his dream house. Edwards also claims that he was trying to hide Hunter from Elizabeth Edwards and not from the government or the American public. In contrast, the prosecution needs to establish that Edwards "willfully, personally and routinely asked Mellon for money," and that he was aware of the money Mellon got to Young, which then went to Hunter, during Edwards' presidential bid.

In Hunter's cringe-inducing 2010 photo spread and the accompanying interview with Lisa DePaulo in GQ , she said she was unaware of the $725,000 received from Mellon. (For the record, DePaulo calls Hunter's spirit "a combination of serenity and spunk.") She adds that Edwards' biggest fear would have been Elizabeth, a sentiment she echoed when asked a similar question by Oprah. She told DePaulo:

"He's not afraid of me. He'll tell me anything and everything. Even disclosing to me when women hit on him, and everything that was said, and if he flirted. He has no fear that I'm going to abuse him. And I believe what happened in his marriage is, he could not go to his wife and say, "We have an issue." Because he would be pummeled. So he had a huge fear. Most of his mistakes or errors in judgment were because of his fear of the wrath of Elizabeth. He's allowed himself to be pushed into a lot of things that he wouldn't normally do because of Elizabeth's story line. And the spin that she wants to put out there. He was emasculated. And you know, the wrath of Elizabeth is a mighty wrath."

Further, Hunter told DePaulo, "I was not aware of how much money Andrew was receiving. When I became aware, in May '08, of how much [the late] Fred [Baron] was sending him, I wanted to have nothing to do with Andrew anymore. Because I felt that I was being used [by the Youngs] for them to pocket money. And I wanted no part of it. And I believe when Johnny became aware of that is when he wanted no part of Andrew as well."

Statements like these could serve to help the defense rather than the prosecution, as they support Edwards' claim that he was simply trying to hide his affair from his wife, and that Young was the true beneficiary of the money. Unless Hunter has changed her tune, the prosecution is highly unlikely to call a witness who'd support the other side. However, things may have changed. For one thing, in 2010, Hunter responded to the question "Do you think Johnny will be indicted?" with a firm no: "For what, not firing Andrew Young ten years ago? No, absolutely not. I do not think Johnny will be indicted." Also, in the 2010 interview, Hunter indicates that she and Edwards were still together. In December of 2011, Edwards had reportedly (by The National Enquirer, who broke the story of the affair) asked Hunter to move in with him and even marry him. True or not, if the two are still together, Hunter becomes an even bigger gamble for the prosecution.

Regardless of what she might say, having Hunter testify would turn this trial into an even bigger media circus, but as the ridiculous testimony continues to emerge, if we don't get Rielle, it's starting to seem like a bit of a let-down. The latest Hunter/Edwards tidbit to come out with regard to the trial is that an allegedly smitten Rielle Hunter kept "a poster-sized photo of John Edwards as a little boy" at her home. He had autographed it for her, "Love, John," according to witness testimony from Andrew Young's friend Tim Toben. Further, while Hunter was "on the lam," writes Tara Palmeri in The New York Post, she had wanted the poster and another photo signed "I love you, John" of the two of them stored—a request she'd made to Toben. But none of this is a smoking gun; don't we really want to hear her say what she knows, herself? The question is whether we'll be able to. With prosecutors wrapping up soon, we won't have to wait much longer to find out.