Thank-you for your question.
Polygamy, having more than one wife (or spouse), is illegal in the USA
but that is not to say that is still does not occur - many states find
it difficult to bring prosecutions citing few people willing to give
There are still certain religious sects that believe in having
multiple wives as can be seen in the news clippings below. Your
friend has given Utah as an example due to the high proportion of
Mormons who live in this region - the Mormon religion *used* to allow
a man to have multiple wives. In fact, for Utah to be recognised as a
state of the USA they had to denounce polygamy.
"Even though polygamy is illegal in Utah and banned by Arizona's
Constitution, authorities haven't prosecuted people simply on those
grounds [being polygamous]."
"Polygamy is illegal in the US, but the authorities have been wary of
confronting the FLDS [Fundamentalist Church of Jesus Christ of
Latter-day Saints] for fear of provoking a siege or inviting political
attacks for religious persecution."
"Polygamy is illegal in the US, but the authorities have reportedly
been reluctant to confront the FLDS for fear of sparking a tragedy
similar to the 1993 siege of the Branch Davidian sect in Waco, Texas,
which led to the deaths of around 80 members."
"Polygamy is against the law in the United States, though, due to the
long struggle in the nineteenth century over Mormonism. As a result of
this struggle, the Church of Jesus Christ of Latter Day Saints
condemned polygamy, and, in the early years of the twentieth century,
actually abolished it."
"The outcry against polygamy eventually led to the federal
government's involvement and the enacting of anti-polygamy laws. (The
U.S. Congress made the practice illegal in U.S. Territories in 1862).
[..] Although Latter-day Saints believed that their religiously-based
practice of plural marriage was protected by the United States
Constitution, the U.S. Supreme Court had already specifically held in
1878 that LDS polygamy was not protected by the Constitution, in the
case of Reynolds v. U.S., 98 U.S. 145 (1878), under the longstanding
legal principle that "Laws are made for the government of actions, and
while they cannot interfere with mere religious belief and opinions,
they may with practices." (Id. at 166.)"
The wikipedia article gives an excellent outline of polygamy and its
acceptance in different religions and cultures here:
With regards to your question regarding whether there are millions of
Christian men with more than one wife in the USA, it is difficult to
categorically state this is true or false as there are no statistics
on this as polygamy is an illegal activity (and therefore "does not
exist"). There are always people prepared to break the law and you
will always hear anecdotal evidence of Mr J Doe having more than one
I hope this fully answers your question. Please ask for clarification
if you require any more references pointing towards polygamy being
illegal in the USA.