The race is among the most hotly contested in the nation and could play a key role in who controls the U.S. Senate come January. Mondale will face Republican Norm Coleman, the former St. Paul mayor who was handpicked by President Bush to try to unseat Wellstone. The party had until Thursday to submit a new name for the ballot.
Members of the Democratic-Farmer-Labor Party's central committee met at a downtown hotel Wednesday night and voted unanimously to name Mondale, 74, who served 12 years in the Senate before becoming Jimmy Carter's vice president.
"I understand by a close vote you have nominated me to run for the U.S. Senate," Mondale quipped. "And I want you to know I gladly accept the nomination."
Mondale added: "We need to honor what the people of our state are going through. We need to heal, and my campaign must help in that healing. Tonight our campaign begins. I will be your voice and I will be Paul Wellstone's voice for decency, hope and better lives."
Wellstone, his wife, Sheila, daughter, Marcia, three campaign aides and two pilots died Friday in the crash of their King Air Turboprop in a peat bog on Minnesota's Iron Range en route to a friend's funeral.
"I don't believe there has ever been a moment in our history quite like this," Mondale told the crowd, which interrupted his acceptance speech numerous times with applause and cheers. "Minnesota is raw with grief. We find ourselves still grieving only five days from an election Paul was going to win. The public calendar with unseemly cruelty is forcing us to move forward. Tonight the nation -- the whole world -- is watching Minnesota, not just to see who'll win but to see how we conduct ourselves."
Mondale pledged to support prescription drugs for seniors, abortion rights, a clean environment, education and efforts to shore up Social Security. He criticized the tax cut President Bush rammed through Congress in the opening months of his administration and alluded to the accounting scandals that have rocked the corporate world.
He also noted under Senate rules, if the Democrats retain control of the chamber, he would immediately move into a leadership position.
Earlier in the day, Mondale advised party officials he would run if nominated.
Tuesday night's Wellstone memorial at the University of Minnesota turned into a Democratic pep rally, with Sen. Tom Harkin, D-Iowa, Wellstone's sons, David and Mark, and a former Wellstone student, Rick Kahn, exhorting the faithful to carry on in the late senator's memory and send a Democrat back to Washington.
The tone of the event irked Gov. Jesse Ventura.
"To turn a memorial service into a political rally, I found quite disturbing," Ventura said. Though he initially said he would appoint a Democrat to fill the remainder of Wellstone's term, he reversed himself Wednesday and said instead he would try to appoint a fellow Independent.
A Minneapolis Star Tribune poll of 639 likely voters Oct. 28 showed Mondale leading Coleman 47 percent to 39 percent with 11 percent undecided and a 3.9 point error rate. The last Wellstone-Coleman poll had the incumbent senator ahead 47 percent to 41 percent with 12 percent undecided. That was a sample of 1,048 likely voters Oct. 11-16 with a 3 percent error rate.
Coleman, who had suspended his campaign following Wellstone's death, Wednesday began his sprint to the finish line, beginning the last leg of his campaign at 6 a.m. with a statewide fly-around.
During the campaign hiatus, Coleman taped a new cache of commercials and his communications director, Tom Mason, said in coming days voters will see a "more vigorous and energetic campaign than we've ever seen."
It will be tough to overcome Mondale's elder statesman aura.
Mondale has never lost a campaign in Minnesota. He is seen as a classic New Deal Democrat and strategists see debates as key to defining the candidates and their positions. A debate had been scheduled between Wellstone and Coleman for Friday night but it was not immediately clear whether Wellstone's replacement would keep the appointment.
Democrats Tuesday asked the Minnesota Supreme Court to make sure those who already have cast absentee ballots for Wellstone are not disenfranchised. The Democrats asked the court to order election officials to make new absentee ballots to Wellstone supporters to give them a chance to vote for the new candidate.
Elections officials had said Wellstone votes would not be counted but Coleman votes would. A hearing was scheduled for Thursday.
Notable deaths of 2014 [PHOTOS]