ABOARD THE CNN ELECTION EXPRESS, New Hampshire (CNN) -- Former Sen. John Edwards Thursday said he will accept public financing for his presidential campaign, and challenged his chief rivals for the Democratic nomination, Sens. Hillary Clinton and Barack Obama, to follow his lead.
Former Sen. John Edwards is the first top-tier Democratic presidential candidate to accept public financing.
"This is not about a money calculation," Edwards told CNN senior political correspondent Candy Crowley on his way to an event in Durham, New Hampshire. "This is about taking a stand, a principled stand, and I believe in public financing."
Edwards is battling Clinton, Obama and a handful of others for the Democratic party's presidential nomination.
With the third-quarter fundraising deadline just days away, Edwards emphasized he did not arrive at this decision because his Federal Election Commission report will show a drop-off in contributions from donors.
"First of all, I got the money I need to run a serious campaign," he said. "I hope that the other two will join me. As I've said, Sen. Clinton said she is for public financing so she can step forward and show she actually means it." Watch Edwards explain his decision to take public funds »
Edwards is the first top-tier Democratic candidate to agree to this funding mechanism, and he noted it will include the primary and general elections. Although he has already begun raising money for the general election, federal law requires him to return those funds if he accepts public funding.
Clinton and Obama have also been raising private funds for the general election, but Obama said he would return the money and accept public funding in the general if the Republican nominee agrees to do the same.
In the race for the GOP presidential nomination, Arizona Sen. John McCain has also said that if he becomes the Republican nominee, he would also accept public funding in the general election if his Democratic counterpart does so as well. McCain also recently became eligible to receive public funding during the primaries, and aides have said they are seriously considering that option.
In order to qualify for so-called "matching funds," the public funding program for the primary season, the FEC requires candidates to demonstrate nationwide support by raising $5000 in 20 different states with no individual contribution to exceed $250, a task which poses little difficulty for major candidates like Edwards.
Once qualified, the federal government will match the first $250 from new contributors, provided Edwards adheres to a $50 million national spending limit, as well as spending limits in each state. Candidates may not receive more than about $21 million in matching funds.
Public funding in the general election comes in the form of an $84 million grant given to a major party nominee if the candidate agrees not to raise or spend outside funds.
No general election candidate has ever refused these funds since the program began in 1976, though this year a number of presidential candidates from both parties have indicated they may forego the general election funding.
Edwards also vigorously defended his wife, Elizabeth, who has been critical of Clinton and her policies.
"First of all, I embrace my wife speaking her mind," Edwards said. "She is a strong woman; got her own opinions. She doesn't and should not ask me whether she can express her opinion."
"Does she say some things that are different than what I say? Yeah, of course. We are two different people. We are not the same person. There is nothing unexpected about that. I hope she'll keep speaking her mind." E-mail to a friend