There are two strictly tactical reasons not to vote for Gore. In the short-term his presence in the White House will perpetuate weak liberal opposition to policies (such as economic, environmental, and military) that would have been pursued equally under a Bush administration but against much greater Congressional hostility. And this liberal apathy also applies to voters. (It's no coincidence that Republicans took over the Senate in 1978 and, after losing it again under Reagan in '86, captured both houses in '94). As to the long-term, a Gore victory means the Democratic Party remains firmly tied to corporate interests. If he loses, on the other hand, there's a chance that a genuine progressive will get the nomination next time around. And if not next time, then the time after that. The key is that the New Democrats consistently lose their bids for the White House. With a Republican in charge again, particularly an obvious ingrate like G.W., the midterm elections of 2002 would send at least one house of Congress back to the Democrats.
Ted