My knowledge of Ayn Rand and her philosophy is limited, but growing. Initially my impression is that her teachings are more popular and influential than most think. (ATLAS SHRUGGED, a movie based on Rand's work has been released recently.
In the last year her name has been brought to my attention by Paul Ryan (Republican Vice-Presidential candidate, 2012). In 2005 Ryan told a group of Ryan enthusiasts, "I grew up reading Ayn Rand and it taught me quite a bit about who I am and what my value systems are,... It's inspired me so much that it's required reading in my office for all my interns and my staff." (http://www.csmonitor.com/Books/chapter-and-verse/2012/0814/Paul-Ryan-does-an-about-face-on-Ayn-Rand )
It was criticism of a Ryan fiscal budget for Congress by the U.S. Conference of Catholic Bishops (Roman Catholic Church,of which Ryan is a member) that drew attention.
On April 17 of this year a statement from the bishops criticized Ryan because, they claimed, his budget did not adequately provide for the needs of the vulnerable poor and children. Ryan had said that his fiscal views were informed by Catholic social teaching. (By David Gibson
Religion News Service, http://www.huffingtonpost.com/2012/04/18/ryan-budget-catholic_n_1434919.html)
Ryan argued that big government is a misapplication of the Catholic principle of "solidarity", and threatens to harm rather than help the vulnerable. (By Will Wilkinson Aug 22, 2012 5:30 PM CT, http://www.bloomberg.com/news/2012-08-22/paul-ryan-can-be-a-catholic-and-still-worship-ayn-rand.html
Solidarity is a foundational principle in the Social Teaching of the Church. "Catholic social teaching proclaims that we are our brothers' and sisters' keepers, wherever they live. We are one human family....
"The principle of solidarity leads to choices that will promote and protect the common good. Solidarity calls us to respond ... to personal, individual misfortunes and to social structures that work toward social justice. --Robert C. Maloney. (http://cm-ngo.net/TenFoundationalPrinciples.html)
Contrast that with Ayn Rand's moral view:
"If any civilization is to survive, it is the morality of
altruism that men have to reject. What is the moral code
of altruism? The basic principle of altruism is that man
has no right to exist for his own sake, that service to
others is the only justification of his existence, and that
self-sacrifice is his highest moral duty, virtue and value.
"Do not confuse altruism with kindness, good will or
respect for the rights of others.... The irreducible primary
[tenet] of altruism, the basic absolute, is self-sacrifice
which means; self-immolation, self-abnegation, self
-denialm, self-destruction—which means: the self as ak
standard of evil, the selfless as a standard of the
good." (Ayn Rand http://www.brainyquote.com/quotes/authors/a/ayn_rand.html#YVThKs0FD8u5sQsC.99
It is simplistic to rest the issue of moral behavior on these two statements. But the best known Western statement of moral behavior is the Jewish commandment: Love God and love your neighbor as yourself. Particularly it is important in both moral dictums (Jewish & Rand) that one love one's neighbor. The real dividing line is "What does it mean to love one's neighbor".
Classic Christianity teaches, feed the poor, clothe the naked, heal the sick. Ayn Rand seems to offer a "tough love" formula: If you create dependency in the lifestyle of the poor, naked and sick, you are actually doing more harm than good.
This is the dilemma for Paul Ryan. If he comes upon a wounded person by the side of the road, does he minister to him/her? Or, does he leave the person to survive by themself? Jesus says "Care for them out of love." Ayn Rand says "You may care for them, but not out of a obligatory mind. You are under no moral obligation to do so. And you especially have no obligation to care for that person, particularly, if it involves sacrifice (self-immolation) on your part.
The terms "collectivism" and "individualism" also fit into this discussion. It is my bias that the Democratic Party takes a collectivistic approach while the Republican Party follows the individualistic line.