When it comes to electing the president, the modern campaign era has its roots 95 years ago when North Dakota held the first presidential primary. CQ Politics looks back and charts for you, election by election, how this process grew over the last century into the long and sprawling campaigns that have become part of the political landscape. This second in a series covers 1968-72.
1968:
1972:
Part One: 1912-64
Part Three: 1976-84
Part Four: 1988
Part Five: 1992
Part Six: 1996
Part Seven: 2000
Part Eight: 2004