You don't even have to use the regex inside of a split:

use strict;

while (<DATA>) {
  my @elements = split;
  print ">", join(':', @elements), "<\n";
}
1;

__DATA__
1     1234    gg123456789  000-12345-1234-111
12    1234    gg123456789  000-12345-1234-111
123   1234    gg123456789  000-12345-1234-111
[download]

split's behavior with no args will do what you want, with the bonus of ignoring leading/trailing whitespace. See perlfunc.