Democratic voters in Connecticut rejected one of their party's most senior politicians, Sen. Joe Lieberman, for a political newcomer in the nation's first major test of the depth of anger over the Iraq war. But Lieberman, who was targeted for his strong support for the Iraq war and for his close ties to President George W. Bush, pledged to run as an independent in an attempt to hang on to his Senate seat in November's general election. "I'll always take the calls of friends, but my mind is made up," Lieberman told NBC's "Today" show Wednesday. "I'm going forward. I'm going forward because I'm fed up with all the partisanship in Washington that stops us from getting anything done." Asked if there was anyone who could call and get him to change his mind, Lieberman replied: "Respectfully no. I'm committed to this campaign." In Tuesday's primary elections, which were held in five states, voters were choosing their party's candidates for the November election. In Connecticut, voters chose Ned Lamont, a millionaire with virtually no political experience who ran on his opposition to the Iraq war. Lamont won with 52 percent of the vote, or 146,061 votes, to 48 percent for Lieberman, or 136,042, with 99 percent of precincts reporting. Lieberman conceded the primary but, undaunted, said he would file papers Wednesday morning to run as an independent. "For the sake of our state, our country and my party, I cannot and will not let that result stand," he said. Lieberman's rejection was a stunning defeat for a veteran politician who only six years ago was the Democrats' choice for vice president. He has held his Senate seat for 17 years, and Tuesday's result made him only the fourth incumbent senator to lose a primary since 1980. The outcome was also seen as a rebuke from Democratic voters who are demanding that their party's lawmakers more forcefully challenge President Bush on Iraq and other issues. Those campaigning against Lieberman played and replayed video of a kiss President Bush planted on Lieberman's cheek after the 2005 State of the Union address. "Tonight we voted for big change," a jubilant Lamont told supporters. The millionaire owner of a cable television company will face Republican Alan Schlesinger, a former state lawmaker, in the general election. Lamont won with 52 percent of the vote, or 146,061, to 48 percent for Lieberman, with 136,042, with 99 percent of precincts reporting. Turnout was projected at twice the norm for a primary election. Lamont supporters predicted victory in November. "People are going to look back and say the Bush years started to end in Connecticut," said Avi Green, a volunteer from Boston. "The Republicans are going to look at tonight and realize there's blood in the water." Two other incumbents in Congress lost primaries Tuesday. In Georgia, Rep. Cynthia McKinney, a fiery congresswoman known for her conspiracy theories about the Sept. 11 attacks and a scuffle this year with a US Capitol police officer, lost a runoff for the Democratic nomination. In Michigan, moderate Republican Rep. Joe Schwarz lost to a conservative in a Republican primary. But Connecticut's results posed questions that went far beyond state lines. Senate Democratic Leader Harry Reid, New York Sen. Hillary Clinton and other officials are expected to endorse Lamont. New Jersey Sen. Frank Lautenberg last week suggested that Lieberman drop plans to run as an independent if he loses by a wide margin. "I think he really has to take a look at what reality is," Lautenberg said. Sean Smith, Lieberman's campaign manager, said Lieberman was prepared to go forward with an independent run no matter what the primary outcome. "This is bigger than the party now," Smith said. On the final day of the race, Lieberman accused his opponent's supporters of hacking his campaign Web site and e-mail system. Lamont said he knew nothing about the accusations.