The Fifth Party system started in 1932, with the election of Roosevelt. It was followed by Democratic/liberal dominance in politics.
It arguably ended with the election of Nixon in 1968, which was followed by Republican/conservative dominance in politics. So arguably, 1968 was the start of the 6th party system.
Is it possible that in 2008, the election of Barack Obama started the 7th party system, and we are in for another 2 decades of Democratic/liberal dominance?
Obama? Not yet. He could be a portent, but... an electoral map of 2020 looks more like that of 2000 than like that of 2000 than like that of 2008.
The extreme regional divide in voting, in which Obama won by a landslide in enough states in which to win the election (the tipping-point state for Obama was Iowa, where he won by 9.54%) but lost a raft of states by even larger numbers isn't sustainable over twenty years. OK, the pattern has held for four elections... Obama was a fine President, but you-know-who followed him.
We are in transition from an era in which regional divides were slight (Clinton-era elections) to... whatever. Parties do not have their own internal realignments unless they are losing elections on a large scale consistently, as did the Democrats in 1980, 1984, and 1988. One bad election (1964 for the Republicans, 1972 for the Democrats) may teach the lesson to not rely solely upon the Party base. Supporters of Goldwater and of McGovern were as fervent as any voters... but that is about what the Parties got with little else in those years. Just think of it: in 1972, West Virginia (which then had voted reliably for Democratic nominees for President) went 62-36 for Nixon despite being heavily unionized.
It is still possible to see Obama as an anomaly in the same sense that Eisenhower was an anomaly between the New Deal and the New Frontier. Demographic trends say more about political trends than do political values.
