While demographic trends favor the Dems in presidential elections, midterm elections are quite different. The electorate in midterm elections is decidedly smaller, older, whiter, more disciplined votes, more conservative, therefore much more Republican than is generally the case in presidential elections. Further, the party out of power tends to gain seats in Congress in midterm elections, this especially the case in the 6th year of an incumbent administration. Consider the following:
In 1958, the sixth year of the Eisenhower Administration, the Democrats scored a huge victory in the midterm elections that year.
In 1966, the sixth year of the JFK-LBJ Administrations, the GOP scored a huge victory in the midterm elections that year.
In 1974, the sixth year of the Nixon-Ford Administrations, the Dems scored a huge victory in the midterm elections that year.
In 1986, the sixth year of the RR Administration, the Dems scored a huge victory in the midterm elections that year.
In 1998, the sixth year of the Clinton Administration, the GOP did not score such a huge victory, primarily because it did so in the 1994 midterm election and there was little left for them to gain that year.
In 2006, the sixth year of the GWB Administration, the Dems scored a huge victory in the midterm election that year.
Polls fluctuate all the time. Historic trends, however, remain relatively constant and do not bode well for the Dems this November, a situation made even worse for them when one considers all of the US Senate seats they must defend this year in red states carried by both McCain and MR and where BHO’s poll ratings are well below the national average.
Gained I believe 47 House seats, but Hugh Scott, Edward Brooke, Thomas Kuchel, Charles Percy, Howard Baker, Jr., and many others kept the Senate liberal even with its Democrat majority.