WASHINGTON - With control of the Senate at stake, former Vice President Walter Mondale is expected to answer Democratic pleas and run to replace Sen. Paul Wellstone of Minnesota, killed in a small plane crash last week, party sources said on Sunday.

Mondale, the Wellstone family's top choice to succeed the 58-year-old lawmaker, has told party leaders he will announce a decision after a memorial service on Tuesday in Minneapolis for the two-term senator, the party sources said.

"I think there would be overwhelming support in Minnesota for his candidacy," Senate Majority Leader Tom Daschle, a South Dakota Democrat, told CBS's "Face the Nation."

Democratic aides said Daschle was among those who urged Mondale to run in the Nov. 5 congressional election. Others included fellow party leaders, labor leaders and Wellstone's family. Wellstone, his wife and daughter were killed in the crash; his two sons, Paul Jr., 37, and Mark, 30, were not on the plane.

Mike Erlandson, chairman of the Minnesota Democratic-Farmer-Labor Party, said the party's central committee would meet on Wednesday to decide on a new candidate to replace Wellstone. The state has set a Thursday deadline.

Erlandson told Reuters the Wellstone family had spoken with Mondale about running. "The senator's family asked the vice president and the vice president gave no indication that he would not accept it if offered," Erlandson said.

He told "Fox News Sunday" Mondale was the "preferred choice of the Wellstone family, which I think is very important."

White House spokesman Ari Fleischer said President Bush had no comment on the political impact until Democrats formally name a replacement. "It's still appropriate to let the people of Minnesota grieve," Fleischer said.

Democratic sources said the feeling was that Mondale, if he was not going to run, would have advised Democratic leaders by now so they could find someone else.

"The sense is that he is going to do it -- and that he is the one who could win," one source told Reuters.

SENATE AND HOUSE UP FOR GRABS

With Democrats holding a one-seat margin in the Senate, any one of a half dozen razor-close races could decide who controls the chamber when a new Congress convenes in January.

Control of the U.S. House of Representatives will also be up for grabs on Nov. 5. Republicans now hold a six-seat majority in the 435-member chamber.

Wellstone, one of the Senate's leading liberals, was locked in a neck-and-neck race for re-election against Republican Norm Coleman, a former mayor of St. Paul, when the small plane went down in bad weather on Friday in northeast Minnesota. Seventeen victims' family members placed flowers and other mementos at the marshy crash site near the town of Eveleth on Sunday.

Also killed in the crash were three campaign aides and two pilots. The accident is being investigated by the National Transportation Safety Board. NTSB officials said on Sunday at a news conference that they were puzzled by a late turn the plane made just prior to the crash.

Transportation Safety Board Acting Chairman Carol Carmody said the last radar contact showed the plane drifting to the south when it should have been headed west toward the runway. "We don't know why the turn was occurring. That's what we hope to find out. We find the whole turn curious," Carmody said.

Bill Walsh, deputy executive director of the Minnesota Republican Party, said Mondale should expect a battle if he becomes the Democratic nominee.

Many voters might see a race between Mondale and Coleman as a choice between an "elder statesman and a place-holder or an up-and-coming candidate who actually wants the job and is working for it," Walsh told the Minneapolis Star Tribune.

A number of other names have been mentioned as possible replacements for Wellstone on the ballot, but Mondale, who will turn 75 in January, was widely viewed as the front-runner.

Mondale served in the Senate from Minnesota before he became President Jimmy Carter's vice president in 1977. In 1984, Mondale was the Democratic presidential nominee in a failed bid to stop Republican Ronald Reagan from winning a second term. He later served as Democratic President Bill Clinton's U.S. Ambassador to Japan.

On "Fox News Sunday," Democratic Sen. Joseph Lieberman of Connecticut said he would welcome a Mondale Senate candidacy.

"It would be greatest tribute to Paul Wellstone's memory if somebody of the stature and purpose and statesmanship and honor of Walter Mondale would pick up the torch," Lieberman said.