A top contributor to John Edwards‘ failed presidential bid was killed just as it appeared he might be called to testify before a federal grand jury probing Edwards’ campaign finances.

Wealthy Texas attorney John O’Quinn died in a one-car accident on Oct. 29 in Houston.

The grand jury in Raleigh, N.C., was considering calling O’Quinn and other major Edwards’ contributors in order to complete its investigation, a top government source in Washington, D.C., told The ENQUIRER.

John O’Quinn was one of Edwards’ biggest contributors and also a close friend of Fred Baron, who was Edwards’ national finance chairman.

Baron allegedly paid hush money to Edwards’ mistress Rielle Hunter and to Andrew Young, Edwards’ former loyalist who took part in the cover-up surrounding the ex-senator’s out-of-wedlock baby with Rielle.

Said the government source: "While there’s no indication of wrongdoing in O’Quinn’s death, it’s weird timing that he was suddenly killed with the grand jury still investigating whether Edwards had broken any campaign finance laws when paying Rielle."

Edwards has denied paying hush money, but O’Quinn’s violent death adds yet another strange twist to the incredible saga of the slick politician’s rapid fall.

 "There’s absolutely no indication that Mr. O’Quinn did anything wrong – or knew about hush money or even knew John Edwards was having an affair," the DC insider said.

"But as a top contributor – AND a close friend of Baron – he was among several individuals that the grand jury was considering calling to testify."

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