Updated

Politicos on both sides of the aisle are pondering just what effect independent candidate Ralph Nader (search) may have on the 2004 presidential election — a race that could hinge on the number of votes the independent candidate pulls.

On Monday, Nader announced a 10-state campaign swing he is embarking on between now and Election Day, which will include Alabama, Connecticut, Louisiana and New York as well as key swing states like Pennsylvania, Michigan and Wisconsin.

"We're trying to get as many votes as possible, which means we're going into states that are characterized as safe states, battleground states and states that fall in between," he said at a Washington news conference.

Nader has long disputed the charge that he will be a "spoiler" for the Democrats in November. Critics have said his candidacy cost Democrat Al Gore the presidential election in 2000 when the former vice president lost by just a few hundred votes in Florida, where the liberal Nader got 97,000 votes for his Green Party candidacy.

Some analysts warn that John Kerry (search) should watch his back and be wary of the so-called "Nader factor," but Kerry's advisers say they're not stressing about it.

"I don't think Nader's going to be a factor in this election," senior Kerry campaign adviser Debra DeShong told FOX News. "They know what's at stake in this election and we feel very confident all those undecided voters are going to come home to John Kerry."

But Bush-Cheney campaign spokesman Kevin Madden said the Kerry camp's actions speak louder than words.

"I think if the Kerry campaign wasn't worried about them, they wouldn't be engaged in litigation all around the country to keep Ralph Nader off the ballot," Madden said. "It clearly shows they're worried somehow."

Hundreds of prominent Democrats have called for Nader to drop out of the race and have urged liberal voters not to support him; Nader has had to claw his way into the competition in many states and has accused Democrats of participating in "dirty tricks" to keep him off the ballots. The Kerry camp says Republicans are helping Nader's campaign for the GOP's benefit.

"Ralph Nader is about as on the far left as can you be, and Republicans around the country have been funding his effort to run for president because they think it somehow hurts John Kerry," said Kerry campaign adviser Joe Lockhart (search).

Winning is not the essential aim of Nader's White House bid.

"Our long-range goal is to break up the two parties," Nader said during the Monday press conference. "[The two-party system] is a menace and subversion of our democratic processes and it's basically sold our elections and our government to commercial interests."

Nader told FOX News that he is not concerned that he might deprive Kerry a chance to become the next president of the United States. Instead, he said his focus has been going around the country to expose the corporate ties of President Bush (search), who he claims is "marinated in oil."

Nader said Democrats are the "worst offender in getting competing candidates off the ballot line," though Republicans are the "worst offender in getting voters off the rolls." And, he added, the country's election machinery is "a mess."

"I'm trying to make this a major issue in America, trying to deepen the substance of the presidential campaign and raise its tone. And all these politicians are engaged in trivia and gossip," Nader told Tony Snow during an interview on "The O'Reilly Factor."

"All I know is I'm trying to go around the country so that the people can win, so that we break up the two-party system."

Nader is on the ballot for sure in 33 states. In seven states, he is off the ballot, though can be written in. His status is uncertain in several other states, including Michigan and Ohio. He has been booted from the ballot in Oregon, Arkansas and New Mexico and his name won't be seen in three of his top four vote-getting states from 2000: California, Massachusetts and Texas.

A Pennsylvania state court recently ruled that tens of thousands of petition signatures the candidate submitted are flawed or just plain bogus. Petitions were apparently filled with false names like Mickey Mouse and Fred Flintstone, leaving Nader thousands of signatures short of what is required.

Asked if he thought he could carry any state in the presidential election, Nader replied, "of course not. The system is rigged."

In Oregon, a battle has been brewing over thousands of signatures being disqualified on technicalities by Oregon Secretary of State Bill Bradbury, a Democrat and big Kerry supporter. One judge accused Bradbury of creating new rules to throw out valid signatures. But two weeks later, the state's Supreme Court overruled once again, tossing Nader off.

"The Nader folks were not following all the rules. And you know, those of us who do this day in and day out, year in year out, chafe a little bit at that," said Paige Richardson, Oregon director of the Kerry campaign.

Since then, the U.S. Supreme Court has refused to stay the Oregon Supreme Court ruling. So now the Nader campaign is asking the justices to review the validity of the secretary of state's action.

"The two parties have entangled us in their insidious schemes and motivation. We're just saying look, get off our backs. Let us just compete," Nader said.

Republican insiders say that Nader could shift support from Kerry one way or another and cause the Massachusetts senator to lose valuable votes.

"It's a problem for Kerry and he's got to be aware of and he's got to … be very sure-footed over the next few weeks, and keep from pushing people over to Nader," said GOP strategist Ed Rogers.

Rogers said that any of the Midwestern states considered swing states, as well as some in the Rocky Mountain region where the races are considered competitive, could see more of a Nader effect than in other regions. "Yeah, he could make a difference and it's got to worry and fluster the Kerry campaign," Rogers added.

AP-Ipsos polling indicates Nader's supporters tend to look a lot like Kerry's, although they are somewhat more likely to be young and white. Some older progressives say they believe that the cultural hero of the 1970s and 1980s has lost his way.

In the 2000 presidential election, the consumer crusader got nearly 3 million votes nationwide. Today, he's drawing 1 or 2 percent support in national polls, which would translate to around 1.1 million to 2.2 million voters based on last election's turnout. He does register as high as 4 to 6 percent in some recent surveys in Maine, New York, Minnesota and Wisconsin. His support is waning, experts say, in part because a growing number of Democrats are disillusioned by the spoiler role.

"They want the vote to count," said pollster John Zogby. "The stakes are very, very high [and]we've really polarized into two separate nations this year more than we were in 2000."

Kerry backers are hopeful that is the case and that remaining Nader loyalists are mostly people who have never voted, and wouldn't have supported their candidate anyway. Still, analysts say 1 or 2 percent of the vote could make the difference in close races like Florida, where Nader is definitely on the ballot.

Some political observers say Nader's hat is still in the ring for the mere reason of rocking the election-year boat.

"I think if the Democratic Party had cloned Ralph Nader and nominated him, the other Ralph Nader would run against him," said former White House counsel Jack Quinn. "This whole thing is ego-driven in my opinion."

FOX News' Dan Springer and The Associated Press contributed to this report.