GREENSBORO, North Carolina — The judge declared a mistrial Thursday in the John Edwards trial after jurors failed to reach a verdict on five out of six charges against the fallen US political star.

Edwards was found not guilty of one count of using campaign donations to hide his pregnant mistress as he sought the Democratic presidential nomination in 2008. A mistrial was declared on the five remaining counts.

The disgraced politician saw his career collapse after he fathered a child with videographer Rielle Hunter in 2007 and then lied about their affair to his cancer-stricken wife, Elizabeth, and the public.

The 58-year-old former North Carolina senator had faced up to 30 years in prison and $1.5 million in fines if convicted of intentionally using nearly $1 million from two wealthy donors to hide his affair.

"This says it all," his father Wallace told reporters at the court, pointing to a smile on his face that showed the family's relief that a four-year ordeal could be coming to an end.

It was not immediately clear if the prosecution would pursue a retrial.

The mistrial ruling capped a confusing and dramatic day at the court in Greensboro, North Carolina as jurors struggled to convince Judge Catherine Eagles that they were unable to reach a verdict on most of the charges.

The judge appeared surprised when the foreman originally announced that a verdict had only been reached on one count, concerning the alleged illegal use of a 2008 donation from banking heiress Rachel "Bunny" Mellon, now 101.

Edwards faced another count of misusing a donation from Mellon in 2007 as well as two similar counts of misusing money given by wealthy Texas lawyer Fred Baron, who died in 2008.

A fifth charge alleged conspiracy between Edwards and his one-time aide Andrew Young, who initially claimed to be the baby's father just before an American tabloid revealed the affair. A sixth count accused Edwards of illegally filing campaign finance reports.

After a short recess, Eagles ordered the jurors to return to their deliberations for the rest of the day to see if they could reach a unanimous decision on all counts.

"There is no reason to believe that any future trial could produce better or more decisive evidence," Eagles said, as a hunched-up Edwards, accompanied by his daughter Cate, looked on, rubbing his temples nervously.

Jurors had been deliberating for nine days in the case that laid bare the extramarital affair that the Democratic presidential candidate embarked on during his second bid for the White House.

The defense was adamant enough time had been spent, but the prosecution believed the jurors should return to their deliberations.

Within an hour of being asked to resume, the jury sent a note to the judge saying they had exhausted all possible options and were deadlocked on the five remaining counts, US media reported.

Edwards appeared relieved as he read the note then passed to him in court. The judge called the jurors back to the courtroom and declared a mistrial on the five remaining counts.

Prosecutors were pinning their hopes for conviction on a key interview in which Edwards publicly admitted the affair for the first time but denied being the father of Hunter's baby girl, despite insisting he wanted to tell the truth.

The interview aired in August 2008, after his presidential bid ended. Just days earlier, Edwards was photographed cradling Hunter's baby girl, Frances Quinn, at a Beverly Hills hotel. But he refused to publicly recognize that he had fathered the child until January 2010.

The defense introduced evidence during the trial showing that much of the funds -- about $800,000 of it -- ended up in the hands of Young, and much of that went towards the construction of the aide's $1.6 million North Carolina home.

Defense attorneys say Edwards did not ask for the money that was used to hide the affair, and that the contributions were unrelated to the campaign.

Legal experts saw the prosecution as risky due to the complicated nation of campaign finance law.

[John Edwards via / Flickr]