The House of Representatives refused to extend the Foreign Espionage Act, provoking a letter from the Attorney General stating that the country "is now more vulnerable to terrorist attack and other foreign threats" because lawmakers failed to act.
According to the San Francisco Chronicle, Democrats denounced the letter, saying the administration is "further politicizing the debate" even as it refuses to allow the extension of existing authority while the House and Senate work out differences on a complex new bill.
The Senate had passed the Bill in question, 68 to 29. McCain voted for that Bill. Obama and Clinton did not vote. (Florida's Democratic Senator Bill Nelson voted for it.)
The main issue seems to be whether to confer retroactive immunity from lawsuits on telephone companies who cooperate with the government. The Senate version confers that immunity.
A day or two before the Senate vote, Senators Dodd and Feingold presented an amendment to strip the Bill of the retroactive immunity provision. That amendment was defeated, but Obama voted for it. Clinton did not vote.