The revelation that the National Security Agency has been collecting the phone records of millions of Americans under the Patriot Act has divided some of the law’s original supporters over whether it is being used appropriately. Though most have defended the government's actions, some supporters are worried about the activity and are asking the administration for answers.

Perhaps most outspoken so far, Sen. Lindsey Graham, R-S.C., on Thursday expressed his support of the mass collection of phone records that was exposed by the Guardian newspaper on Wednesday.

“I'm glad the NSA is trying to find out what terrorists are up to, overseas and inside the country,” Graham said Thursday during an interview on “Fox and Friends.” “I'm a Verizon customer. I don't mind Verizon turning over records to the government if the government is going to make sure that they try to match up a known terrorist phone with somebody in the United States. … I'm glad the activity is going on, but it is limited to tracking people who are suspected to be terrorists and who they may be talking to.”

The Guardian reported Wednesday that the NSA, with the approval of a secret court, was collecting metadata from Verizon on all customers' calls, both in the United States and between the U.S. and foreign countries, over a three-month period, under Section 215, or the business records provision, of the Patriot Act. Data included where and when calls were made but not their content.

Graham insisted that the government wasn’t using the phone records for anything else. “I'm sure we should be doing this,” he said.

Sen. Dianne Feinstein, D-Calif., a longtime supporter of the Patriot Act, added Thursday that the court order represented a three-month “renewal” of an ongoing practice authorized under the business records section of the Patriot Act. “Therefore it is lawful, it has been briefed to Congress,” said Feinstein, who chairs the Senate Intelligence Committee.

Rep. Mike Rogers, R-Mich., chairman of the House Intelligence Committee, also defended NSA's actions, and asserted that this records collecting program has actually thwarted a terrorist attack. "Within the last few years this program was used to stop a terrorist attack in the United States. We know that. It's important,” Rogers told reporters Thursday.

As the Guardian article noted, the mass collection of phone records is likely what Sens. Ron Wyden, D-Ore., and Mark Udall, D-Colo., were referring to when they sent a letter to Attorney General Eric Holder in 2012 saying that “Americans would be stunned to learn how secret court opinions have interpreted” the business records section of the Patriot Act.

But not everyone who voted for the Patriot Act, and the 2011 reauthorization of key provisions that included the business records provision, are comfortable with the government’s mass collection of phone records as detailed in the Guardian’s report.

Rep. Jim Sensenbrenner, R-Wis., a key architect of the original Patriot Act in 2001, said Thursday that this surveillance activity goes beyond what the business records provision intended to allow.

“As the author of the Patriot Act, I am extremely troubled by the FBI’s interpretation of this legislation,” Sensenbrenner said in a statement. “While I believe the Patriot Act appropriately balanced national security concerns and civil rights, I have always worried about potential abuses. The bureau’s broad application for phone records was made under the so-called business records provision of the act. I do not believe the broadly drafted FISA order is consistent with the requirements of the Patriot Act. Seizing phone records of millions of innocent people is excessive and un-American.”

Sensenbrenner sent a letter to Holder Thursday, asking him if the NSA’s data collection is consistent with his and the FBI’s interpretation of the business records provision, and whether Holder believes that provision has any limitations at all.

“Why they would need that much data puzzles me,” Sen. Jeff Flake, R-Ariz., who supported the Patriot Act’s reauthorization as a Hosue member in 2005 and 2011, said on MSNBC Thursday. “That was a surprise and raises some questions that I think we ought to answer.”

Flake said that if the government can demonstrate that this kind of phone records collection is necessary to national security “then perhaps it's okay.”