The major difference are the issues of gay rights and women rights. Democrats support both, and are strong advocates of all human rights. They oppose the war. They advocate raising our taxes, but the Republican's do it too, just more of a hidden form.
Republican's provide tax breaks for the rich, especially estate taxes. They also heavily support defense spending. They claim they don't want to raise taxes, but they suck it out of us by raising food prices, gas prices.......other tax methods. Political platforms change, and all politicians make promises they don't always keep.
So in the end, I don't see a real difference. Both political parties have hidden agenda's and manipulate the public for their own special interests.