If she does attack Perry using the dishonest line (always used by Democrats) that social security is not a Ponzi Scheme, and that Perry wants to kill it, this dishonesty and cynicism would lose her a lot of conservative support. She might not be elected Representative again, let alone President.
I think she has her eye on a Romney VP slot.
I agree that it is a dangerous gamble.
She is fully aware that Rick Perry has no intention of gutting SS.
He intends to fix it.