The standard Oath of Allegiance for Naturalized Citizens prescribed by the U.S. Citizenship and Immigration Services concludes with the phrase "so help me God". Las Vegas Now reports that at a naturalization ceremony on in Nevada on Friday former Swiss citizen Thomas Kaenzig convinced federal officials to permit him to take the oath without that final phrase. Kaenzig is a Raelian. Raelians believe that humans were created by a race of extraterrestrials. As a pacifist, Kaenzig was also permitted to exclude from his oath the promise to bear arms on behalf of the United States.
UPDATE: 8 CFR Sec. 337.1(b) specifically permits deletion of "so help me God" from the oath for reasons of conscience. [Thanks to posted Comment from Scott M.]