The correct spelling is with one r.
So, what is the reason for the discrepancy?
Mike Darow (January 8, 1933 – December 7, 1996) was a Canadian-American television game show host best known for hosting the 1968-1970 ABC run of Dream House, the 1985-1988 Canadian-produced run of the Bob Stewart game show, Jackpot (seen in the U.S. on the USA Network), and Club 6 from 1960-1962.http://www.enotes.com/topic/Mike_Darrow
From 1959 until the Fall of 1965, Darow worked as an on-air disc jockey in Toronto at radio station CHUM. One of the zany promotions CHUM had Darow do was to sit in a car attached to a crane at a Toronto car dealers lot. Darow was an excellent singer and had two songs charted on the CHUM chart, "The Battle of Queenston Heights" which was a parody of Johnny Horton's "Battle of New Orleans" and "The Brotherhood of Man", which was recorded by the CHUMingbirds on the Quality label. The CHUMingbirds were Mike Darow, fellow CHUM DJ's John Spragge and Bob McAdorey, along with CHUM copywriter and sometimes fill-in DJ, Garry Ferrier. Ferrier wrote both songs, along with many others, including "Ringo Deer" and "Like A Dribbling Fram", both of which were released on Capitol Records of Canada ("Like A Dribbing Fram" was credited to Race Marbles - who was Ferrier).
Although many people misspell Mike Darows' name with two 'r's', there is only one. That happened because "The Battle of Queenston Heights" record label misspelled his name (the two 'r's') on the label and the myth has been perpetuated ever since. A check of any CHUM chart from 1959 until 1965 or a peek into "The CHUM Story" book by Allan Farrell will show you there was only one 'r' in Mike's name.