South Carolina Republican Sen. Lindsey Graham on Tuesday requested the identities of any Obama administration officials who may have sought intelligence information on members of President Trump's 2016 and 2017 campaign and transition teams.

The senator's request comes days after the acting director of national intelligence, Richard Grenell, released a list of names of Obama-era officials who potentially received intelligence reporting connected to Michael Flynn, Trump's first national security adviser, in the months following the 2016 election.

"Given the extensive number of requests for the unmasking of General Flynn's name during this short time period, it raises the question of whether these or other officials sought the unmasking of the identities of other individuals associated with the Trump campaign or transition team," Graham wrote in a letter to Grenell and U.S. Attorney General William Barr.

However, it is not possible for officials to have known what names had been redacted, or masked, in security agencies' reports. As NPR reported last week:

"Reporting about those communications is used in myriad ways by investigators, analysts and policymakers. But for the sake of security and, to some extent, privacy, the reports undergo 'minimization' before they're circulated widely.

"So a report might not say: 'Foreign Minister So-And-So talked about the election this week with John Smith.' It would say he talked with 'U.S. Person 1.'

"Certain officials of sufficient stature can ask for Person 1's identity to be 'unmasked' to more fully understand what's taking place in the reporting."

Still, Graham, chair of the Senate Judiciary Committee, requested information from Grenell and Barr regarding inquiries between Nov. 8, 2016, and Jan. 31, 2017, into Trump campaign affiliates, including Trump himself, Donald Trump Jr., Ivanka Trump, Jared Kushner, Corey Lewandowski, Paul Manafort, Steve Bannon, Kellyanne Conway, Sam Clovis, Chris Christie, Carter Page and George Papadopoulos.

Graham also seeks an "explanation as to why the list released on May 13th by [Grenell's office] did not contain a record showing who unmasked General Flynn's identity for his phone call with [then-Russian Ambassador Sergey] Kislyak."

The topic of unmasking has sparked attention in recent weeks in light of Barr's Justice Department seeking to drop charges against Flynn that stem from the federal investigation into Russia's interference in the 2016 election — this despite Flynn's admission of lying to the FBI about his communications with Russian officials.

On Thursday, Graham's Judiciary Committee will vote on whether to give him the authority to subpoena documents and communication related to the FBI's investigation into any links between Trump associates and Russian officials.

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