Back during the days of the Democratic Majority (1932-1994), their show of power consisted of the Boston-Austin connection. For instance, during their time of power, their was Speaker Sam Rayburn (D-TX) and Speaker Thomas "Tip" O'Neill (D-MA). However, since 2004 that connection has been frayed and these new Dems are not the party of old.
A) Three Elections - Let us start with 1964. If you look at a map , you can see that LBJ won a majority of the Southern sates (From TX to MD). By 1976, all Carter won was the Southern states. By 1980, Carter lost all the southern states but GA. 1964 was the last high tide for the Democrat party in the south. Remember, after FDR, any President could not get elected without the south. LBJ was an admirer of FDR and worked to continue that connection between Southern Conservatives and Northern Liberals. In 1994, after the Republicans solidified Congressionally what was occurring Presidentially. Ten years later, the Dems didn't fight in the south at all.
B) Military culture and Global War on Terror - Thanks to Kerry's remarks last week, the real view of the Dem party and the military can be seen. Since the Tet offensive in 1968 and Kerry's remarks in 1972, the Democrat party has taken an Anti-war stance that it has never left. What would happen if the Dem's win Tuesday during the GWOT? They will make Israel the new Czechoslovakia to Hamas and Hezbollah. They will allow the terrorists to re-group in Iraq and make it Afghanistan 1995 (who was President then?).
C) Southern Culture - Most Democrats have no problem insulting southerners (even though they need their votes). Redneck culture is just as important as Hip-Hop culture in this big nation. The "solid South" was a bedrock in Democrat politics until 1980, and then has not turned back. The GOP has a bulk of the country as it's starting point. The mid-Atlantic and New England states are losing population. It is also too expensive for most people to live in the Pacific west. Until the Dems learn to speak Southern, they will lose.