They served 1903 (Edward Everett Hale) and 1909 (Ulysses Grant Baker Pierce). I don't know what religious view he had, probably fairly but not entirely traditional and quasi-Christian. Probably transcendental.
http://en.wikipedia.org/wiki/Chaplain_of_the_United_States_Senate Here is what Wikipedia says about Hale:
Combining a forceful personality, organizing genius, and liberal practical theology, Hale was active in raising the tone of American life for half a century. He had a deep interest in the anti-slavery movement (especially in Kansas), as well as popular education (especially Chautauquas), and the working-man's home. He was a constant and voluminous contributor to newspapers and magazines. He was an assistant editor of the Boston Daily Advertiser and edited the Christian Examiner, Old and New (which he assisted in founding in 1869 and which merged with Scribner's Magazine in 1875), "Lend a Hand" (which he founded in 1886 and which merged with the Charities Review in 1897), and the Lend a Hand Record. He was the author or editor of more than sixty books—fiction, travel, sermons, biography and history.
Hale first came to notice as a writer in 1859, when he contributed the short story "My Double and How He Undid Me" to the Atlantic Monthly. He soon published other stories in the same periodical. The best known of these was "The Man Without a Country" (1863), which did much to strengthen the Union cause in the North, and in which, as in some of his other non-romantic tales, he employed a minute realism which led his readers to suppose the narrative a record of fact. These two stories and such others as "The Rag-Man and the Rag-Woman" and "The Skeleton in the Closet," gave him a prominent position among short-story writers of 19th century America. His short story "The Brick Moon", serialized in the Atlantic Monthly, is the first known fictional description of an artificial satellite.
. . . .
He is quoted as having said: “I am only one, but still I am one. I cannot do everything, but still I can do something; and because I cannot do everything I will not refuse to do the something I can do.”
http://en.wikipedia.org/wiki/Edward_Everett_HaleAs for Pierce:
Ulysses Grant Baker Pierce (1865-1943) a Unitarian minister, served churches in both Pomona, California, and Ithaca, New York. He received degrees from Hillsdale College and George Washington University, including an honorary DD. From 1901 to 1942, Pierce was the pastor of All Souls Unitarian Church in Washington, D.C. He held the position of chaplain of the United States Senate from 1909 to 1913, under President Taft. Pierce also published The Creed of Epictetus (1916) and The Soul of the Bible (1917).
http://www.hds.harvard.edu/library/bms/bms00646.htmlMore on Pierce:
The faith of a stoic being the teaching and philosophy of Epictetus synthetically arranged and edited /--by Ulysses Grant Baker Pierce. (1915)
* Pierce, Ulysses Grant Baker.
Abstract
Typescript.. Thesis (Ph. D.)--George Washington University, 1915.. Includes bibliographical references.
Publication details
Repository OCLC's Experimental Thesis Catalog (United States)
http://en.scientificcommons.org/5145933