In the 2000 Florida election, Ralph Nader received 97,488 votes, while Al Gore lost the state (and, therefore, the presidency) by 537 votes to Mr. Bush. For many Democrats here on DKos that is all they need to know. Nader cost Gore the election.
But to stop there and decide that nothing else matters is to also leave the "reality-based community" label behind, because there are many other numbers that also matter.
I've made many of the exact same arguments myself over the years, usually for naught. Good times, good times. One more thing I would add: if you paid attention to left/Green media in those days — and I did — you would have absorbed a consistent message: if you live in a battleground state, play it safe and vote for Gore, but if you live in a safe state, go ahead and vote for Nader (and there was even this scheme in an attempt to get the best of both worlds). Obviously, no one thought Nader had a chance to win the election. The goal was merely to win 5% of the national vote, which would allow the Green party to qualify for federal funds in the next election. In other words, exactly the sort of incremental, long-term, strategic planning that mainstream Democrats are always insisting idealistic third-partiers need to practice. Not that it saved them from entering Democratic lore as the archetype of treason.