Supermajority rule gave southern Democrats an effective veto over any presidential nominee for many years, until the rule's abolition at the 1936 Democratic National Convention. A majority vote, or more than half the votes cast, is a common voting basis. Instead of the basis of a majority, a supermajority can be specified using any fraction or percentage which is greater than one-half (i.e., 50%). It can also be called a qualified majority. Common supermajorities include three fifths (60%), two thirds (67%), and three quarters (75%). A two-thirds vote, when unqualified, means two-thirds or more of the votes cast. This voting basis
Ladder of thirds tonic or central note." (Middleton 1990, p.203) [while pentatonic scales are analyzed as piled fifths] They are "commonplace in post-rock 'n' roll popular music – and also appear in earlier tunes". (Middleton 1990, p.203) Examples include The Beatles' "A Hard Day's Night", Buddy Holly's "Peggy Sue" and The Who's "My Generation", Ben Harney's "You've Been A Good Old Wagon" (1895) and Ben Bernie et al.'s "Sweet Georgia Brown" (1925). Ladder of thirds A ladder of thirds (coined by van der Merwe 1989, adapted from Curt Sachs) is similar to the circle of fifths, though a ladder of thirds differs in