The 2012 election will not resemble either the 1964 or the 1968 Presidential contests.
More likely, the 2012 election will be more like 1968 or 1972 battles.
Granted, the Republican voters — not the "Republican Establishment" — gathered around Richard Nixon. Conservative favorite Ronald Reagan would have to wait until 1980. Yet in both elections, the Democratic party was saddled with a Progressive incumbent, then candidate, whose legislative platform and policies were so out of step with the rest of the nation, that the GOP nominee faced little opposition making the case to "the silent majority" of voters.
Today, we are witnessing the disillusioned and disgusted "silent majority" vocally voicing outrage with the current President's policies. From the grounded Tea Party to the nascent Occupy Wall Street Movement, President Obama's liberal policies having been tried and found wanting. Just like the entrenched liberals of 1968 and 1972, the Democratic party will be pressed not only to run against a coalesced GOP, but also run against the 2008 campaign of hope and change which has not come to pass.