It is one of those things that I don't think makes a whale of a lot of
 difference.  Typically, at least in fairly large historical societies, the
 board proposes a slate and just the folks who attend the annual meeting vote.
 They, the membership, have very little chance to really make a difference.
Early in my career, I worked for a society that had a fair sized endowment
 fund.  The 'young turks" used to dream we could round up a thousand or so new
 members (at $25 a pop) and stuff the annual meeting with our folks and grab
 control of a $20 million dollar fund for our own evil,  but history related,
 purposes.