WASHINGTON (AP) — Fuming lawmakers pointed fingers at one another and President Barack Obama on Thursday as negotiations over raising the national debt limit entered a perilous endgame. Federal Reserve chairman Ben Bernanke warned of economic damage, and an anxious Wall Street envisioned catastrophe if the U.S. defaulted on its obligations.The president’s blunt declaration that "enough is enough" as the previous evening's talks ended did nothing to quell the rancor as a new day of positioning and posturing played out.Senate Majority Leader Harry Reid stood on the Senate floor Thursday and sniped that House Minority Leader Eric Cantor shouldn't even be part of the talks anymore, noting that the Virginia Republican has been called "childish." Not long after, Senate Republican Leader Mitch McConnell stood to serve notice that the debt problem belonged squarely in Obama's lap."Republicans will not be reduced to being the tax collectors for the Obama economy," McConnell said.