ONTARIO, OH — Arizona Sen. John McCain delivered a stinging rebuke of President Barack Obama's handling of the terrorist attack on an American consulate in Libya, saying the commander in chief is either "engaged in a massive cover-up" or is "grossly incompetent."

The 2008 GOP presidential nominee focused his remarks on the Sept. 11, 2012 attack in Libya rather than Hurricane Sandy at an event in battleground Ohio that had been billed as a "storm relief and volunteer appreciation" event.

"This president is either engaged in a massive cover-up deceiving the American people or he is so grossly incompetent that he is not qualified to be the commander in chief of our armed forces. It's either one of them," McCain told Romney volunteers gathered here at a Victory Center.

Though the mention of the attacks has faded from Republican presidential nominee Mitt Romney's stump speech, it remains a hot button for conservatives who feel the death of four Americans was a result of negligence on the part of the White House. Democrats have condemned the accusations as an attempt by the right to politicize the tragedy, a notion McCain dismissed when speaking to reporters.

"I think it's interesting to note that when there was a success, such as when, thank God, we were able to get bin Laden, the administration poured out every single detail, even details that put American lives in danger," McCain said. He later added: "It is my obligation to the men and women who are serving to get the full story out to these four brave Americans have families. They deserve to know why their sons were sacrificed in the needless fashion."

As McCain motivated volunteers at Romney's Ohio headquarters, the GOP nominee held a relief event to collect supplies for those affected by Hurricane Sandy. Obama cancelled campaign events on Tuesday, and Romney scratched an earlier event in this state, a move McCain called "appropriate."

The 2008 presidential candidate said he believes the storm "froze everything in place while this terrible tragedy fixated the attention of the American people. Now i think they're ready to get back into this campaign."

Also joining McCain was Republican National Committee Chairman Reince Priebus, who encouraged Ohioans to bring supplies to Victory Centers throughout the state. They are two of many surrogates who will be hitting the Buckeye State between now and Election Day. The focus now is turning out the base and getting as many early votes as possible before Nov. 6.

Asked to compare conservative enthusiasm now to at this point four years ago, McCain said, "I hate to admit it but it's much stronger than in 2008. That's just a fact."