You need lc also: 
use warnings;
use strict;

while (<DATA>) {
    s/(\w+)/ucfirst lc $1/e;
    print;
}

__DATA__
 BELLMONT NY
 NEW YORK NY

[download]

outputs: 

 Bellmont NY
 New YORK NY

[download]

In reply to Re: Capitalize only the first letter of the first word in a string by toolic
in thread Capitalize only the first letter of the first word in a string by Anonymous Monk

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