The risk for the GOP is that the party can split. The only thing that deters nonaligned candidates such as Bloomberg from running is that they cannot compete with the massive campaign engines of the established parties. So the only way to do so is by co-opting (part of) the establishment. How effective has John Boehner been as whip? The same lack of cohesion undermines the party as a whole. Who determines what the republican party is other than its members?
2016 will be an interesting race. Jeb Bush could be the only candidate capable of rallying the GOP into a coherent whole aimed at the executive again. At least, until the elections are over. A Jeb Bush presidency could exacerbate the fractures in the GOP and lead to its demise. A president has to rule and Jeb Bush would be closer to many in the democrat party than to the many libertarians, tea party radicals and extreme conservatives that inhabit the house of representatives.
A fracture has seemed imminent for years, it still seems imminent.