Who Invited You?

As I read the news of Ralph Nader's announcement, in the background my computer was playing the Donna's song "Who Invited You?" I found this a fairly aggressive bit of irony, and so I decided to go with it, especially since the next song up on my random cue was "Running On Empty" by Jackson Brown.
Ralph Nader is running for President of the United States - again. He has run in the last two elections, and there are those who still hold that his campaign siphoned off just enough votes from Al Gore's base in 2000 to allow Pinhead to slither in on the side. Just as he did in 2000 and 2004, Ralph is criticizing the top White House contenders for being too close to big business and he pledges to "shift the power from the few to the many."
"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." He also criticized McCain, Clinton and Obama for not fully supporting Medicare and not doing enough to stem the bloated military budget. His third party campaign will only accept money from individuals.
I don't blame Ralph for being disenchanted. I don't blame him for Al Gore losing his election, or stealing the presidency from John Kerry four years later. 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 Democrat. "So naturally, Republicans would welcome his entry into the race." Thanks for the support, Mike!
Hillary referred to Nader as "a passing fancy", and Barack Obama said, "In many ways he is a heroic figure and I don't mean to diminish him. But I do think there is a sense now that if somebody is not hewing to the Ralph Nader agenda, then you must be lacking in some way." But, as most of the other candidates agreed, it is a free country, and at 73 years old, Ralph meets at least one of the criteria for being President of the United States. He has been running for the office, off and on, since 1992. Is there any reason to doubt his sincerity?