The answer to this question is at least somewhat in the eye of the beholder because you can argue that there are very few socialist programs or very many.
Socialism per se is a system in which the government controls the production and distribution of goods and services. It does so in an attempt to ensure that everyone has a decent standard of living and (in some cases) to ensure that no one has “too much.” Given this definition for socialism, we can see that almost any government program can be seen as a step towards socialism. Even the most revered programs, like Social Security and Medicare clearly have socialist aspects. Even these programs take money from some and distribute it to others in an attempt to improve their lives.
This means that essentially any government program (including things like tax breaks for interest on mortgages for middle class families) smacks of socialism. Therefore, the term has little true meaning in terms of American political discourse and is simply a term of abuse to be used against any government program that is seen as too intrusive or too redistributive in the eye of any particular beholder.