Sen. Lindsey Graham, R-S.C., threw cold water on the whistleblower complaint on Thursday but demanded to know who in the White House spoke with the whistleblower and why they didn't file a complaint on their own.

"It is imperative we find out which White House official talked to the whistleblower and why. Why didn’t they lodge the complaint?" he asked on Twitter.

He seemed to refer to the White House officials the whistleblower complaint cited as being "deeply disturbed" by a call in which President Trump urged Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden.

WHISTLEBLOWER COMPLAINT ON UKRAINE CALL RELEASED, ALLEGES TRUMP SOLICITED FOREIGN 'INTERFERENCE' IN ELECTION

The White House released a rough transcript of the call on Wednesday, revealing that it contained no evidence of a quid pro quo for foreign aid. The House Intelligence Committee continued pressing the issue on Thursday, as Acting Director of National Intelligence Joseph Maguire testified before the panel.

Republicans have panned the report as benign and alleged Democrats were grasping at straws in trying to attack the president. Graham seemed to agree, calling the report a "pig in a poke" bought by Democrats.

He also blasted the whistleblower complaint as an obvious effort to hurt the president. "As to the other matters in complaint: Clearly a coordinated effort to take second-hand information to create a narrative damaging to the President," he tweeted. "When I think of whistleblower complaints I generally think of someone with first-hand knowledge of the events in question."

As Graham, the chairman of the Senate Judiciary Committee, noted, the whistleblower filed the complaint without witnessing the events himself. Rather, the individual relied on second-hand accounts.

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He also appeared to think Democrats were bluffing on impeachment, arguing that if the whistleblower report was as big a deal as they made it out to be, the House should vote to pursue an impeachment inquiry.

House Speaker Nancy Pelosi, D-Calif., announced on Tuesday that she would launch an official inquiry but the House has yet to vote on official proceedings.