Consumer advocate Ralph Nader said Sunday he will run for president as a third-party candidate, criticizing the top White House contenders as too close to big business and pledging to repeat a bid that will "shift the power from the few to the many." Nader also ran as a third-party candidate in the 2000 and 2004 presidential elections. He is still loathed by many Democrats who call him a spoiler and claim his candidacy in 2000 cost the party the election by siphoning votes away from Al Gore in a razor-thin contest in Florida. Nader vociferously disputes the spoiler claim, saying only Democrats are to blame for losing the race to George W. Bush. Nader, 73, said most people are disenchanted with the Democratic and Republican parties due to a prolonged Iraq war and a shaky economy. He also blamed tax and other corporate-friendly policies under the Bush administration that he said have left many lower- and middle-class people in debt. "You take that framework of people feeling locked out, shut out, marginalized and disrespected," he said. "You go from Iraq, to Palestine to Israel, from Enron to Wall Street, from Katrina to the bumbling of the Bush administration, to the complicity of the Democrats in not stopping him on the war, stopping him on the tax cuts." "In that context, I have decided to run for president," Nader told NBC television's "Meet the Press." Nader also criticized Republican candidate John McCain and Democrats Barack Obama and Hillary Rodham Clinton for failing to support extending the Medicare health insurance program to all Americans or cracking down on Pentagon waste and a "bloated military budget. He blamed that on corporate lobbyists and special interests, which he said dominate Washington, D.C., and pledged in his third-party campaign to accept donations only from individuals. "The issue is do they have the moral courage, do they have the fortitude to stand up to corporate powers and get things done for the American people," Nader said. "We have to shift the power from the few to the many." Republican presidential candidate Mike Huckabee, speaking shortly before Nader's announcement, said Nader's past runs have shown that he usually pulls votes from the Democratic nominee. "So naturally, Republicans would welcome his entry into the race," the former Arkansas governor said on CNN. Nader won 2.7 percent of the national vote as the Green Party candidate in 2000, but his percentage dropped to just 0.3 percent as an independent in 2004, when he appeared on the ballot in only 34 states.