Thanks to the new law, they also have to deal with anyone that wants to try and torpedo the other side.  

If it's a close nomination race between Perlmutter and Polis, while the (R) nomination is a runaway, the new rules make it easy for more people (including many that usually vote for the opposing party) to cross over and cast a torpedo vote for the candidate least likely to win a general election.

Of course sometimes that backfires, like it did for many D's that cast votes for Trump in (R) open primary states, thinking that would help Hillary win.  Oops.