to create more red states? To break up a state, it requires consent from both the state's legislature and the U.S. Congress, according to Article IV, Section 3 of the U.S. Constitution. Doesn't seem like a problem since Republicans control Congress.
Look at it as cells breaking up to multiply (mitosis). Red state legislatures can't possibly resist that idea to create more Republican Senate and House seats, not to mention more electoral votes.
The sky is the limit: 15 more red states and 30 more Republican Senators. With 15 more Republican state legislatures, they can also call for a Constitutional Convention.