The judge upheld the objection and the jury was brought back after discussions of the letter had ended.
Also today, a staffer testified that Edwards' mistress caused so much turmoil on his presidential campaign that one staffer messaged headquarters from the road pleading to be let off the "traveling freak show."
The comment came amid testimony that Edwards' Hunter was lavishly paid by the campaign although the video webisodes she made were so poorly done that the campaign refused to use them.
Former campaign manager Nick Baldick told the court today that Hunter earned more than $250,000, for producing just a handful of campaign videos for the Web.
It was an arrangement he "concluded was probably not a very good deal," but which Edwards insisted on maintaining despite Hunter producing videos that did not "portray Mr. Edwards very well."
"I thought the webisodes were a disaster," Baldick told the court.
The staff was also roiled by their growing perception that Edwards was having an affair with Hunter and her growing demands for access.
One staffer, Ryan Montoya requested Baldick "free me from this traveling freak show" after frustrating interactions with Hunter and her production partner.
Edwards was asked by senior advisers in 2006 to stop traveling with Hunter to squash romance rumors. From then Baldick was supposed to approved all travel Hunter did with the campaign, but whenever Baldick would refuse to approve Hunter for a trip he would get a call from Edwards, he said.
"Nick, she's going on this trip," Baldick quoted Edwards' repeated order to him.
Edwards, however, quietly celebrated a small victory for his defense when a crucial witness, Mellon's lawyer, said he believed that Mellon's cash was intended as a friendly gift and not as a political contribution.
"It was a good morning for the home team," Edwards whispered to his 30-year-old daughter Cate following the testimony of Alex Forger, an attorney who has represents Mellon.
Forger testified today that Mellon gave Edwards $725,000 during the his presidential campaign out of an abiding sense of loyalty and friendship and not as a political contribution.
"In later years she had few close friends," Forger said of his longtime client. "Her husband had died, and her daughter was ill. She took a liking to John Edwards as she had done with others. She liked him as an individual, as a person, not because he was a candidate."
Mellon gave Edwards all that money because "she felt very strongly for John Edwards," adding, "she wasn't interested in becoming secretary of state."
That testimony contradicts the prosecution's narrative that Mellon gave Edwards the money as a political contribution, which he used in part to hide his mistress and their love child.
Forger said he first learned Mellon was giving Edwards money, transferred through one of Mellon's friends to one of Edwards' aides, when a personal check Mellon had written for $150,000 bounced.
When he asked Mellon what the money was for, she said it was a personal gift to Edwards and not a political contribution.
Forger also said that when he first contacted Edwards in August 2008 to ask about the money, Edwards denied knowing about his aides receiving money from Mellon, but later admitted it was for his benefit.