Mitt Romney is not the first Mormon presidential candidate. That honor goes to Joseph Smith the Mormon founder and prophet. Smith declared for the presidency in 1844: "Tell the people we have had Whig and Democrat presidents long enough. We want a president of the United States." He even had a catchy campaign song:
Kinderhook, Kass, Kalhoun, nor Klay
Kan never surely win the day.
But if you want to know who Kan
You'll find in General Smith the man.
Not catchy enough, however, Smith was murdered by an angry mob only months into his campaign. (No voter apathy in the 19th century!)
Mormons were a subject of curiosity and controversy in the Pacific Northwest. There was a short-lived Mormon mission to the Indians named Fort Limhi near Lemhi Pass from 1855-1858. After the mission was disbanded there were frequent (unfounded) rumors of Mormon and Indian shenanigans in the interior of the Northwest. In 1858 the Pioneer and Democrat fretted that "there is good reason for believing that the Mormons are aiding and abetting the savages in a war of extermination of what they designate--Gentiles." By January of 1861 the Portland Standard was fretting that Mormon agents were active among the Indians of the interior "inciting the various tribes into open hostility" against whites (though the paper admitted the rumor "does not come well authenticated.")
But by the 1880s most of the northwest was swept by anti-Mormon movements, culminating perhaps in the famous Idaho Test Oath of 1884, which used the practice of polygamy to effectively disenfranchise all Idaho Mormons. Appeals went all the way to the Supreme Court, which upheld the law. By 1893 Idaho lawmakers repealed the act, but anti-Mormon language remained in the Idaho constitution until the 1980s.
[The above cartoon shows Idaho as a sword-bearing angel casting out the leather-winged abomination of Mormonism. It appeared in the Portland newspaper The West Shore and is reprinted in Carlos Schwantes' The Pacific Northwest: An Interpretive History.]