Josh Brumberger, now 33, described accompanying Edwards to the Virginia home of Rachel "Bunny" Mellon in December of 2005. Soon after, the wealthy heiress made the first in a series of substantial donations.
Brumberger's testimony during the campaign finance corruption trial is a key part of prosecutors' efforts to establish the timeline of the affair and efforts to conceal it. Prosecutors said Edwards used money from Mellon, who's now 101, and another wealthy donor to hide the mistress. Edwards' attorneys have said he didn't know it was being used to hide her and that another former aide, Andrew Young, spent it on his dream house.
On Wednesday, Brumberger also described how Edwards and his associates made efforts to stay in touch with Mellon, including calling on her birthday and sending flowers. Brumberger said that it was typical for Edwards to have "call time" with major donors.
Months after the first meeting with Mellon, Brumberger was traveling with Edwards when he called her on her birthday from North Dakota. Young had sent an email to Brumberger reminding him that the call needed to be made, and Brumberger later responded that it had gone well.
"JRE called. Bunny is still in LOVE," Brumberger wrote in the email, referring to Edwards by his initials.
After the email was displayed in court on Wednesday, prosecutors asked Brumberger what it meant.
"I believe what I meant by that is Ms. Mellon was still supportive of Mr. Edwards's causes," Brumberger testified to laughter in the courtroom.
Brumberger was also with Edwards the night that his mistress, Rielle Hunter, introduced herself in the bar of a New York hotel. He hadn't yet discussed that night during the morning testimony.
Brumberger was pushed aside by Edwards after he tried to convince the married candidate to stop the affair.
Edwards has pleaded not guilty to six counts related to campaign-finance violations. He faces up to 30 years in prison and $1.5 million in fines if convicted on all counts.
At issue are payments from Mellon and a wealthy Texas lawyer, Fred Baron, who served as Edwards' campaign-finance chairman. Young, who testified last week under an immunity agreement, has acknowledged that he kept about $1 million of $1.2 million in payments from the two campaign supporters.
Prosecutors have said Mellon offered under-the-table cash to cover Edwards' personal expenses after the candidate was embarrassed by media reports that campaign funds were used to pay for $400 haircuts.
"From now on, all haircuts, etc., that are necessary and important for his campaign, please send the bills to me," Mellon wrote to Young in April 2007.
The following month, Edwards' mistress, Rielle Hunter, informed the candidate she was pregnant. According to the account in Young's 2010 tell-all book about the affair, Edwards was unable to access his own money to support Hunter without his wife, Elizabeth, finding out. So, Young says, Edwards decided to take Mellon up on her offer.
The eventual candidate's courtship of the donor, though, began on the December day described by Brumberger from the witness stand. He recalled his impressions upon first arriving.
"It's beautiful -- a gigantic piece of property in the horse country of Virginia. Rolling hills," he said.
The visit began with some confusion on the part of Mellon. While they were waiting for her, Edwards had excused himself to go to the bathroom. When Mellon walked into the room, she saw only the much younger Brumberger and began talking to him as if he were Edwards.
After that, Mellon recounted to them her visits to the Kennedy White House, which included her helping to plant its rose garden.