Greensboro, North Carolina (CNN) -- A former aide to John Edwards testified Thursday about an unexpected pronouncement from a campaign videographer: She and the presidential candidate were in love.
But Edwards later told him he was not in a relationship with Rielle Hunter, John Davis said.
"He told me she was crazy and that he denied there was an affair," according to Davis. The assistant said he took Edwards at his word.
Jurors on Thursday also heard from an interior designer who served as the conduit for hundreds of thousands of dollars of alleged coverup money from a wealthy Edwards benefactor. Bryan Huffman testified that neither he nor the donor knew that the money was to be used to conceal Edwards' extramarital affair with his mistress.
Prosecutors say Edwards broke federal law by accepting about $725,000 from heiress Rachel "Bunny" Mellon and more than $200,000 from Fred Baron, a now-deceased Texas lawyer who was his finance chairman.
The money was used to pay for Hunter's living and medical expenses, travel and accommodations to keep the mistress out of sight while Edwards made his second White House run in 2008, prosecutors say.
Edwards is accused of hiding the money from the public and the Federal Election Commission, which polices political contributions, by filing false and misleading campaign disclosure reports.
Davis' testimony was the latest from Edwards staffers about their former boss's relationship with Hunter. Edwards, who was married at the time, eventually admitted to having carried on an affair with the woman and fathering her child.
A former campaign staffer said Thursday that Edwards flatly refused to sign a document in December 2007, under penalty of perjury, declaring that he was not the father of Hunter's child.
Mark Kornblau testified Edwards had been told that if he signed the affidavit, the National Enquirer might consider not running a story about his affair with Hunter.
Legal experts say that by refusing to sign the document, Edwards demonstrated that while he was willing to lie in public about the affair, he was not willing, in this instance, to break the law.
Prosecutors reacted with surprise to the testimony, asking the witness why he never told them about this in pretrial interviews.
Kornblau's response: Prosecutors never asked about the matter.
Davis, the former aide, testified he was surprised to see Hunter at a Detroit hotel in February 2007 because he thought her work as videographer had been completed.
The two exchanged pleasantries in the lobby.
Davis said he rode the elevator for a few floors with Hunter before getting off to avoid a longer ride with her.
"I would have preferred not to have seen her," Davis testified.
Minutes later, Hunter knocked on his door.
Hunter, according to Davis, "told me that she and Sen. Edwards were very much in love" and the candidate was concerned because Davis had seen Hunter in the hotel.
The aide testified he told Hunter that "I did not care about this because I was focused on the campaign."
Davis also testified about a phone conservation involving Edwards after a September 2007 appearance on CNN.
Edwards was talking with a woman whose voice sounded like Hunter's, according to Davis.
Edwards asked the woman on the phone, "Can you tell if you are showing?" the witness said.
Earlier testimony indicated Hunter believed she became pregnant in early May 2007.
Davis also suggested that Edwards came close to pulling out of the race after an argument with his wife, Elizabeth Edwards, who has since died. The candidate instructed Davis to pull together a conference call in which Edwards was to announce he was suspending his campaign.
But Elizabeth Edwards canceled the call, according to Davis.
Thursday afternoon's testimony featured Huffman, the interior designer from Monroe, North Carolina.
Huffman, a longtime friend of Mellon, said he understood money was welcomed because "Mr. Edwards needed financial support for a poverty center."
Mellon also saw Edwards as a possible presidential candidate when she started making the payments, Huffman said.
In all, Mellon who will turn 102 in August, gave $725,000 for something Huffman said she knew nothing about: Payment for Hunter's expenses.
Huffman suggested Mellon didn't consider her donations as specifically intended for the campaign.
The witness elicited a laugh from the courtroom audience when he admitted that Mellon said she knew individual contribution limits the 2008 election cycle but that Mellon considered the limits "a little low."
In 2008, the Federal Election Commission limited an individual to a contribution of $2,300 to each candidate or candidate committee in the primary election and $2,300 in the general election.
Huffman, who said he never took any of the money for himself, talked about how the payments were made.
He described the process for getting cash to one of Edwards' key staffers, Andrew Young, as a "furniture business."
Mellon wrote several checks payable to Huffman ostensibly for a table, chairs and a bookcase. Huffman said he signed the checks, but instead of cashing them, he handed them over to the family of Andrew Young, the prosecution's star witness.
Young's wife, Cheri, endorsed the checks, but signed her maiden name.
Mellon didn't want her lawyer to find out about the checks because he was always on the lookout for examples of Mellon giving away too much money, according to Huffman, who said the whole thing "just didn't feel correct."
Cheri Young testified Monday that Edwards told her that using money from one of his benefactors to pay his mistress's expenses was legal. Young said that she felt "disgusted" after being asked to endorse and deposit checks from Mellon.
Edwards' attorneys have said that Andrew Young was involved in a ruse to extract hundreds of thousands of dollars from donors for his personal use.
The defense argues that the money Edwards received from Mellon and Baron was for personal reasons: to protect Elizabeth and his family from public humiliation. Edwards has said his actions were wrong but insisted that they were not illegal.