He will not help Romney. Conservatives know from his votes in favor of tarp, auto bailout, raising the debt ceiling, increased budgets etc, which are contrary to his "conservative" speeches, that nothing will change with him or Romney. They Paul Ryan "extreme" budget does not balance until 2040.. THATS 28 years from now!! They may not vote or will vote for a third party candidate.
People who are against Romney from the left will surely not change their vote.
Those on the Right who disagree with Obama enough would vote for anyone no matter what the vp stands for.
The Ryan choice will shift the debate to the budget, but the Repubs will never ever do the tough political things (like drastically cut the military and social programs) to save the nation from bankruptcy.
JJ