
Originally Posted by
Matthias
They have no real definition and on many issues no clear stance (among Democrats and Republicans).
That's because since there are only two political parties basically, they are very big tent, meaning they have many different interests (some of them competing) that make up the coalition of Republicans and Democrats.
This is how the parties are broken up (generally of course)
Republicans - Corporations, social conservatives, older, more homogenous
Democrats - Corporations, unions, social liberals, younger, more diverse
It should be noted that corporations actually have a huge amount of influence in both parties. Corporations will often donate to both parties before the election, so that whoever wins, they have an "in" so to speak. Almost every politican that makes it into political office has accepted corporate money. Corporations also have much more power and money than unions. Unions in the US are not at all powerful, especially anymore, compared to Europe. The Healthcare debate was a perfect example of corporate power, as they spent billions of dollars to help "shape" the debate and put commercials on air in favor of their position. Europeans would probably see Democrats as just moderate conservatives, which is what many of them are. There are some "socialists" or "progressives" that could be said to be on the moderate left of the European spectrum, but they are the minority of the Democratic Party. The Republican Party has been going farther right lately, with the far right gaining more control of the party. Moderate Republicans generally are for some government regulation, whereas some of the new teapartiers are pretty extreme (some want to repeal the 14th Amendment or make it legal for private businesses to discriminate based on race again).
Also it should be noted that the Republicans are much farther to the right than most "moderate" rightist European parties. And Democrats in many cases are farther to the right than moderate rightist European parties. So the whole political slant is much more to the right than in Europe.
Libertarians are one of those third parties in a political system where it is practically impossible to have a successful third party. As far as I can tell, Libertarians are mainly made up of these groups:
Libertarians - Orginalists, State's rightists, Isolationists, Semi-anarchists etc. They really don't have corporate donors as they are not worth donating to as they don't have political power. But their platform would be seen as pro-corporate, at it is generally anti-regulation. Whatever their moral beliefs, they don't want government deciding morality (such as gay marriage). This doesn't make them personally socially liberal though, but they could be said to fit into that category. In my experience, many libertarians simply vote Republican or are Republican because there is no real Libertarian option, though some do vote Democrat, depending on their priorities.
So there is a very broad, general overview from my experience of some American political parites.