Rules fights are fun, obscure, and usually well behind the scenes. Not the fight over whether independents (normal speak for California’s "Decline to State" or DTS) can vote in the GOP primary. They can in the Democrat’s primary.
For the most part, this fight is breaking down along ideological lines. Moderates want DTSers to vote. Conservatives do not. There was a forum earlier in the week in California about this issue. The Flash Report has details:
I will mercifully spare you the host of arguments made in support and opposition to such a suggestion, if only because it really boiled down to two fundamental considerations: The practical reality that allowing DTS voters to participate would likely increase the number of votes cast in support of Republicans and, in contrast, the belief held by Fleischman, me and many others in the party that electoral gains are not a sufficient justification for diluting and, in limited exceptions, rejecting fundamental Republican principles.
The interesting question is going to be whether Presidential politics really enters into it.
The room for possible conflict is Rudy Giuliani. Rudy is a moderate who probably does better with DTSers voting. But a good chunk of his in-state infrastructure is from the conservative wing of the party which strongly opposes this change. If the campaign decides that they need DTSers, then will they try to put pressure on their delegates at the CRP convention?
There’s another way that this could play. There is jockeying among the moderates between Rudy and John McCain. Will this become a test of "moderateness" among the moderates?