I'm certainly not an exception. I wouldn't say that I let ideology override reason, but I let it override argumentation and persuasion, which can easily masquerade as reason.

I think that a certain level of stubbornness may actually be a survival trait, because it protects a highly social animal from manipulation and deception.

In modern society, we are deluged with information with a very poor signal-to-noise ratio and many false leads. My approach is to let my short term decisions, such as voting, be influenced to a certain degree by ideology, but let my ideology be influenced over the long term by a preponderance of evidence. This allows me to function without being jerked back and forth by the best debater or hottest news du jour.