From everything I have read and heard, its most likely the FA transcripts, showing Obama applied for financial aid as a foreign citizen. Not seeing this as a real big deal as far as electoral politics. The MSM will say Donald’s docs are forgeries and that it’s more right wing desperation and dirty tricks. Jay Carney will laugh it off in his daily press briefing and that will be that. But Gloria Allred if she does have some crappola to spill will get 24\7 coverage. Won’t matter in the end, R&R win 320 EVs in two weeks
If Trump produces documents, the Obama camp and their MSM lackeys will just claim forgeries and proceed forward, ridiculing anyone who gives it credence. I don’t know that it will make a difference, just like the birth certificate stuff.
But I do think Romney and his advisors are plenty smart enough not to let this distract them.