use strict;
use warnings;
use Data::Dumper;

my %h;
while (<DATA>) {
    while (m/(\w+)\s?:\s?(\S*)/g){
        $h{$1} = $2;
    }
}
print Dumper \%h;
__DATA__
firstName : firstValue
          Name2: Value2
          Name3:Value3            Name4:value4
Name5:             Name6: