Michael,
It's not clear to me that "broadening the base of the democratic party by reaching out to the disinfranchised" would insure that Clinton would "get slammed" for moving right. Rather, it might only have the effect of creating an alienated rank and file party membership as Clinton (or Gore, or Bradley) continues their steady march rightward. A broad base only matters if it has a way of insuring that it has some way of holding the leadership accountable for policies which the leadership acts on.
I don't think the leadership has any intention of allowing this to happen-even if it could be shown to be a winning strategy for the dems. The leadership after all, is deeply principled-the operative principle being that wealth needs to be continually transferred from the population to corporations at any cost. They will stand for this principle even if it means losing elections. (N.B. losing an election does not mean losing access so long as the loss was "principled" according to the above definition.)
Best,
John