Fox executives have millions of reasons to be happy with "Joe Millionaire" - 18.6 million of them. The premiere episode of the reality series attracted 18.6 million viewers Monday, making it the most-watched show of the night, according to Nielsen Media Research. "Joe Millionaire" resembles ABC's "The Bachelor" in that a group of young women compete for the affections of an eligible man. The difference is that Fox's bachelor, Evan Marriott, is a construction worker who posed as a wealthy scion with a $50 million inheritance. The watercooler-worthy concept hooked viewers, especially women between the ages of 18 and 34. "Joe Millionaire" drew 34% of that key age group watching television Monday at 9 p.m. "The word of mouth for this show was enormous," said Preston Beckman, executive vice president of Fox. The audience for "Joe Millionaire" was larger than any episode of "The Bachelor," with the exception of that show's finale. Male viewers were the difference. "The Bachelor" was watched by an average of 4.5 million men, while "Joe Millionaire" attracted 6.4 million.