Edwards campaign spokesman Jeremy Van Ess told WRAL Tuesday night that Edwards will make an official announcement at 4 p.m. Wednesday at Broughton High School in Raleigh.
Edwards was John Kerry's last major rival for the Democratic presidential nomination. His decision effectively ended a short, relatively polite nominating campaign.
Word of Edwards' decision to drop out spread as he addressed supporters in Atlanta, where his remarks sounded like a campaign valedictory.
"We have been the little engine that could," Edwards told supporters in Atlanta Tuesday night, "and I am proud of what we've done together, you and I."
A lot of supporters seemed stunned, looking at each other as if to ask: "What did he just say?" Others were left in tears, very disappointed that it appeared Edwards was bowing out of the race.
Others still were optimistic, hoping that Edwards may end up as a vice presidential nominee in November.
Earlier Tuesday -- well ahead of the pivotal Super Tuesday voting results -- Edwards had said he would continue his campaign regardless of how he fared in Tuesday's 10 primaries. He also announced his schedule for Wednesday, when he planned to go to Texas.
A few hours later -- more than two hours before Van Ess' statement -- Edwards' national campaign chairman, Ed Turlington, said: "we think he's going to win hundreds of delegates today."
Turlington said there was no set benchmark for determining if Edwards should continue or not after Tuesday.
"One of the things I've learned in politics is not to set up some standard before people even vote," Turlington told WRAL's David Crabtree. "But we . . . hope and believe he can get some wins, and then we'll see where we are.
"Then, as you know, next week, there are four southern states where John can do well if he gets the necessary showing of strength tonight."
When asked if Edwards would be in Texas on Wednesday, Turlington said: "I hope so. We'll determine that by tonight's results, and I believe he will."
The results, however, showed that Edwards' best decision was to drop out of the race.
Kerry won primaries in New York, Rhode Island, Ohio, Massachusetts, Connecticut and Maryland by early Tuesday evening and also was favored in California and Minnesota.
Edwards led in Georgia at the time he decided to drop out. But he lost by a large margin in Ohio, which he considered a must-win state along with Georgia.
He later lost Georgia to Kerry.
Former Georgia Governor Roy Barnes introduced Sen. Edwards for perhaps his final speech as a presidential candidate. Edwards came out with his usual smile and thumbs-up to the crowd, but then his stump speech took an unusual turn.
Congratulating Kerry, he said: "he's run a strong powerful campaign. He's been an extraordinary advocate for causes that all of us believe in, more jobs, better health care, a cleaner environment, a safer world.
"These are the causes of our party," Edwards said. "These are the causes of our country, and these are the causes we will prevail on come November."