(Adds interview with Nader)

WASHINGTON, Feb 24 (Reuters) - Consumer advocate Ralph Nader, blamed by many Democrats for their loss of the White House in the 2000 election, said on Sunday he is launching another independent campaign for the White House.

Nader, who will turn 74 this week, announced his longshot presidential bid on NBC's "Meet the Press" saying that neither the Democrats nor the Republicans were addressing problems facing Americans.

Nader called Washington "corporate occupied territory" that turns the government against the interests of the people. "In that context, I have decided to run for president," he said.

Democrats said they do not expect Nader, who also ran as an independent in 2004, to have much of an impact.

"When you get into running for your third or fourth time, I don't think people will pay that much attention to it, and I wouldn't see it having any effect on the race," Virginia Democratic Gov. Tim Kaine said on "Fox News Sunday."

In an interview with Reuters, Nader said he will push the candidates on a number of issues including health care and changing the tax system to shift the burden away from wage earners and put it on things like pollution, tobacco and "Wall Street speculation" and reduce taxes on wages.

Nader dismissed Democratic criticism of his latest bid for the White House.

"For anybody who thinks that the third try is something that should be demeaned, it represents persistence, it represents never giving up the struggle for justice," Nader said. "The forces of injustice never take a holiday."

Nader ran for president in 2000, when he got about 2.7 percent of the national vote as the Green Party candidate. Many Democrats blamed Nader for draining votes from Democrat Al Gore and tipping the election in favor of Republican George W. Bush. He also ran as an independent in 2004, but got only a tiny fraction of the vote.

Nader said he expects to do better this time and will work to get his name on the ballot in all 50 states.

Republican presidential hopeful Mike Huckabee, appearing on CNN's "Late Edition," said he thought Nader could pull votes away from the Democratic nominee.

"Naturally Republicans would welcome his entry into the race and hope that maybe a few more will join in," Huckabee said.

Democratic candidates Sen. Hillary Clinton and Sen. Barack Obama criticized the independent candidate.

"That's really unfortunate. I remember when he did this before, it didn't turn out to well, for anyone, especially our country," she said. "I hope it's kind of a just a passing fancy that people won't take too seriously."

Obama, Clinton's rival for the Democratic presidential nomination, was asked on Saturday about a Nader candidacy. "My sense is that Mr. Nader is somebody who, if you don't listen and adopt all of his policies, thinks you're not substantive," he said. (Additional reporting by Claudia Parsons, Jeff Mason and Nancy Waitz; Editing by David Wiessler) (To read more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at

blogs.reuters.com/trail08/

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