This could weaken them. Doug Mataconis analyzes:
If the Republican primaries in states like California, Florida, and Texas are required to award delegates proportionally, it would throw a curve ball into the nominating process that would have interesting, and unforeseeable, consequences. At the very least, these new rules would seem to favor candidates who have national, rather than merely regional, appeal within the GOP and would also be advantageous for those candidates able to convince voters that they have a chance of winning in November, rather than candidates who appeal to some hard-line ideology.