Updated

Walter Mondale returned to politics Wednesday night as Minnesota Democrats loudly approved the former vice president as a fill-in for the late Sen. Paul Wellstone -- and Republican nominee Norm Coleman started up his campaign again after a brief respite.

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Minnesota Gov. Jesse Ventura was so offended by the political rally that evolved out of a memorial service to honor Wellstone that he said he will try to appoint an independent instead of a Democrat to fill out Wellstone's term until a replacement is certified.

"I feel used. I feel violated and duped over the fact that that turned into nothing more than a political rally ... I think the Democrats should hang their heads in shame," Ventura told Fox News on Wednesday.

More than 800 party representatives, in a special meeting, approved Mondale's candidacy with a boisterous "YEA!" There were no dissenters. Mondale was mobbed as he made his way to the podium to speak.

"Tonight, our campaign begins," Mondale said. "I start it with a pledge to you. I will be your voice, and I will be Paul Wellstone's voice for decency and better lives."

Earlier Wednesday, Mondale ended any suspense about his intentions with a letter to Democratic leaders, declaring himself ready to run if chosen.

"It is with a heavy heart but a great hope for the future that I will pick up the campaign where Paul Wellstone left off," Mondale wrote in a letter to the state party chairman.

Democrats were jubilant at the news. Mondale, 74, is seen as their best shot at keeping Wellstone's seat as they try to hold on or add to their single-seat majority in the Senate.

The news came amid growing concern the results of Tuesday's closely watched election will be delayed at least a day. State and county officials warned that confusion over what to do with absentee ballots would slow things.

Coleman didn't wait for the official coronation of his new opponent: He targeted Mondale as he made campaign stops in three Minnesota cities Wednesday and launched new TV commercials.

"The challenge for the vice president is, what is his vision for the 21st century, how does he expect to get it done," Coleman said at a stop in International Falls. "Nobody hands you anything."

The Minnesota GOP was also very disturbed by the political nature of the Wellstone memorial, and demanded that local media give the party equal time by covering a rally being held Wednesday night at a restaurant in St. Paul.

"It was billed as a memorial service, but it was a planned political rally. And [Democrats] can conduct themselves in any fashion they want, I am not commenting on that. I am simply asking for equal time from all the television stations and radio stations," said Ron Eibensteiner, head of the state GOP.

Bill Walsh, deputy executive director for the party, said that all four of the local network affiliates covered the entire memorial, which lasted from 7:30 to 11 p.m. Public radio and AM radio stations also carried the event.

He said that the party was not looking for the channels to air the entire two-hour rally on Wednesday night, but to broadcast a portion of the event and perhaps a rally that was expected to feature President Bush on the weekend.

It would be "a great equal time gesture," Walsh said.

Prior to Tuesday night's event, Ventura said that he was leaning toward appointing a member of Wellstone's party to replace Wellstone, who died in a plane crash on Friday while headed to a funeral for the father of a state senator. Wellstone's wife, daughter, three campaign workers and the two pilots on board the plane were all killed in the crash in northern Minnesota.

Wellstone, a Democrat, was in the midst of a tough re-election battle against Coleman in a race that could have been a critical contest in determining control of the U.S. Senate.

Ventura said he was disgusted that some of the nearly 20,000 people who attended the memorial service booed Senate Minority Leader Trent Lott, R-Miss., who traveled to Minneapolis along with many other senators, Republican and Democrat, to attend the memorial service.

Lott also left the service early. Ventura said his wife was so upset by the political quality of the speeches that she left the arena on the University of Minnesota campus in tears.

Ventura said he was particularly disturbed by a speech by one of Wellstone's closest friends, Rick Kahn, in which Kahn said to the crowd, "I'm begging you to help us win this Senate election for Paul Wellstone."

"I wanted to hear the sons. But Rick Kahn's [speech], I found his so offensive to me as an independent, or to anyone who is not necessarily going to vote for Sen. Wellstone who still respects him and came to pay their respects," Ventura said. "It drove the first lady to tears."

Packing up boxes on Wednesday, a representative from Wellstone's campaign said that it was unfortunate that the event took on a political tone, but added that the campaign had no control over the speakers, who were selected by family members of the deceased.

Polls appearing in Wednesday's Minneapolis Star Tribune showed Mondale leading Coleman 47 percent to 39 percent, a wider margin than separated Wellstone and Mondale. The poll of 639 adults conducted on Monday, the same day Republicans conducted an internal poll that was criticized by Democrats as callous, found that 98 percent of Minnesotans recognized Mondale's name and 66 percent had a favorable image of him, including several Republicans surveyed.

"I think many people out there -- simply because of who Paul Wellstone was, the legacy Wellstone left, even if they don't agree with Wellstone's politics -- will vote for the Democrat," said former Clinton Labor Secretary and failed Massachusetts gubernatorial candidate Robert Reich.

But Republicans say Mondale, who hasn't been in elected office since 1981, is too removed and too much an old school liberal to represent the state.

Fox News' Steve Brown contributed to this report.