From Conservapedia

In atheistic Britain, people dislike underdogs and tend to root for the contestant who is favored to win. The opposite is true in the Christian United States, where the underdogs have traditionally been the favorites of the people.

However, as the liberal media in the United States becomes increasingly atheistic, victories by underdogs are increasingly met with dismay or disapproval.

The failure by atheists to build hospitals illustrates their tendencies not to help the weak. The underdog epitomizes the weaker side in a contest, and atheists are fine with the underdog losing. Rooting for the underdog is like giving to charity, something that Christians do at a much higher rate on average than atheists.

Here are additional possible reasons why atheists dislike underdogs:

Belief in Survival of the Fittest

Atheists are fervent believers in "survival of the fittest," and this implies that the underdog will lose and should lose.

Atheism Denies Faith and Hope -- the Keys to Underdog Success

Atheism is a denial of faith and hope, but these are essential ingredients to rooting for an underdog.

Atheists are Wannabes, Craving Recognition

Atheists are wannabes, craving recognition by others whom they perceive to be smarter. This leads them to side with the team or candidate who is favored by others, particularly by other atheists.

Clinging to a Belief Against Surprises

The belief system of an atheist clings to a denial that there will be any surprises like Hell. Victory by an underdog is a surprise, which is unsettling for atheists who insist that there must not be any big surprises in an afterlife.

Optimized for an audience IQ of perhaps 105

Atheism is optimized for an audience having an IQ only slightly above average, perhaps 105. That audience can be more easily persuaded that because something is probable, it will happen 100% of the time. This is flawed by not recognizing the possibility of unlikely outcomes, which often result in important upsets. (Such as predictions against the existence of Hell).

Atheism Is About Control

One obvious reason is that atheism is about control. Stalin, a famous atheist in the 20th century, probably did not like underdogs. Underdogs threaten the status quo and the worldview of atheists. Upset victories are unsettling to people like Stalin.

"Militant Atheism" Is a Bullying Ideology

Militant atheism is, obviously, a bullying ideology. For example, it demands censorship of classroom prayer even when everyone in the classroom wants to pray. A bullying attitude is incompatible with rooting for underdogs.

Atheists Cling to "Conventional Wisdom" of (Atheistic) Public Schools

Atheism relies heavily on clinging to "conventional wisdom" as taught in atheistic public schools. The underdog is a counterexample to government-style conventional wisdom.

Atheism is a Self-Centered Ideology; No Room for Underdogs

Self-centered ideologies obviously have less room for underdogs. Atheism is a self-centered belief system.

Atheists Prefer Policies that Thwart Social Mobility

Upward social mobility is much easier in the United States than in atheistic nations, reflecting the very different views of Christianity and atheism toward underdogs.

Atheists Are More Prone to Hate

Atheists often reach their views based upon a dislike or hate of God's existence, for they like to see the nonexistence of god as inevitable. People overcome with so much hate often will also hate the underdog for challenging what they see as inevitable victory of the expected winner.