A Democrat wins in '68 and likely '72. That means the GOP is likely to get stuck with the chalice that is the late '70's.
Not necessarily. It is possible that the Vice President of John F. Kennedy, who was elected in 1968 and easily re-elected in 1972 in this scenario, would win the Presidency in 1976. It is also possible that a Nixon victory in 1960 would either delay the Iranian Revolution (until perhaps 1983 or so), or prevent it from occurring entirely (I know that Nixon was a strong supporter of the Shah, so he may have encouraged the Iranian government to execute Ayatollah Khomeini and other opposition leaders during the 1963 Iranian protests), thus butterflying away the 1979 oil crisis and the Iranian hostage crisis.