Why do christians think they are right?

After all, so many more people in the world AREN'T christian, than ARE. Even though the bible thumpers claim that jee-hu-zus is the sav-hu-yer, and that anyone who doesn't buh-leeve is doomed to some kind of hell, they don't realize that they are preaching ignorance! Can't we all just get along, without discrimination? The hard sell doesn't work, people, and getting mad about it won't make your argument more convincing!