“Thank you, Iowa!”

That was the simple message Tom Harkin wanted Iowa voters to hear Tuesday night as he accepted another six years as U.S. Senator from a lectern at the Hotel Fort Des Moines.

Harkin, an incumbent, defeated Republican challenger Greg Ganske, a U.S. House representative, by a vote of 54 to 44 percent, with 83 percent of precincts reporting.

Green Party Candidate Tim Harthan and Libertarian Richard Moore each came in with 1 percent.

“The politicking stops tonight … I work for all of Iowa,” Harkin told a roaring crowd.

The U.S. Senate race was seen as one where Republicans might have had the chance to win a crucial seat in their bid to the Senate majority party.

“The Senate is deadlocked 50-50,” said James Carstensen, Iowa Rep. Tom Latham’s press secretary, prior to the announcement of Harkin’s victory. “If Mr. Ganske wins, it’s a sign that the Republicans will regain the Senate.”

The victory was decisive despite controversy triggered by a Harkin campaign supporter secretly tape-recording Ganske’s campaign planning sessions in September.

Joshua Reicks, senior in political science and volunteer for the Latham and Gross campaigns, said the scandal did not have the impact it could have had.

“The reason Tapegate was covered so much was because [Ganske] didn’t have a message to project.”

The victory was not entirely unexpected by Republicans.

Roman Lynch, Republican candidate in District 45, said, “Harkin’s an old fox. He knows what he needs to do to win.”

Louis Kishkunas, freshman in political science and member of the ISU College Republicans, agreed.

“[Ganske’s loss] was kind of expected,” he said.

“I think if Ganske just would have been a bit more visible, he could’ve pulled it out.”

Harkin graduated from Iowa State with a bachelor of science in government and economics in 1962. He served in the U.S. House of Representatives for 10 years before winning a seat in the U.S. Senate in 1984. He was re-elected in 1990 and 1996, and now again this year, giving him the distinction of being the first Iowa Democrat to ever earn a fourth Senate term.

During his campaign, Harkin stressed his leadership experience in areas such as health care, education and agriculture.

He differed from Ganske on several key issues, including taxes, prescription drugs and Social Security.

As of press time, Democrats throughout the country were defending their slight majority in the U.S. Senate.

Republican Elizabeth Dole won the Senate seat in North Carolina, and John Sununu, also a Republican, won a Senate seat in New Hampshire. Both states were highly contested.

Other Republican wins in the Senate were: Lindsey Graham in South Carolina, Lamar Alexander in Tennessee, Mitch McConnell in Kentucky, Thad Cochran in Mississippi, John Warner in Virginia, Pat Roberts in Kansas, Chuck Hagel in Nebraska, Jeff Sessions in Alabama, Mike Enzi in Wyoming, James Inofe in Oklahoma, Susan Collins in Maine and Pete Domenici in New Mexico.

Democrat winners were: John Kerry in Massachusetts, Richard Durbin in Illinois, Jay Rockefeller in West Virginia, Joseph Biden in Rhode Island, Jack Reed in Rhode Island, Carl Levin in Michigan and Max Baucus in Montana. Also, Sen. Frank Lautenberg was elected to the Senate in New Jersey, replacing Sen. Robert Torricelli.

— The Associated Press contributed to this article