The Liberal group in Democracy 3 has to be viewed very broadly. What is liberal in one culture is conservative in another, and vice-versa. The liberals, in many regards, follow ‘classic liberalism’. They share some characteristics with real-world Libertarians in that they believe in as little state restriction as possible in many areas. However, they split with them in that they have no problem with government control as long as it is in their favor (just like Conservatives). They are against most religion-friendly policies since they see this as divisive and a bit ‘backwards’. They love advancement in science and an extensive public education system. The reason they are against gun bans is because it restricts a freedom of individual civilians. But they are pacifists and so are against violence in every other way, especially state-imposed violence. When it comes to crime, they prefer rehabilitation and re-education as opposed to punishment. You have to divorce them from the contemporary American ‘liberal’ in some regards, but they are spot on in other aspects.
The Conservatives like you to be tough on crime and almost merciless. They abhor violence except when it is used by the state to punish violent criminals. They value ‘tradition’ very highly. Any attempt to progress society, such as through anti-discrimination policies and the like, is frowned upon. Progress equals ‘moral decline’. They would like the dominant ethnicity, religion, and cultural group to stay in power. This will maintain the status quo of society.
In a similar vein, Socialists are more accurately Democratic Socialists or Social Democrats. ‘True socialists’ would laugh derisively at the same policies that make Democracy 3’s Socialists ecstatic. Also, (at DEFAULT levels) there are higher proportions of them than there are real-world socialists. Basically, they like the government stepping in to help people out and elevating the status of the poor and down-trodden. That describes a lot of people as opposed to those who have no problem with things like corporate tax breaks and private schools. A real-world active socialist would probably call me something like a ‘weak-willed capitalist reformer’. But in the game, I would be heavily influenced by the Socialist ideology.
This is just my understanding of it. Remember that these Voter Groups and all the other game elements have to be generalized for varying nations with different cultural values and political systems. Hope this helps!