But Democratic Senator Richard Blumenthal said that, the "central issue for us, on the Attorney General of the United States, is will he be the people's lawyer or the president's?"
Lindsey Graham, the committee's new chairman, had urged his colleagues to confirm Barr and allow him to take the helm of the Justice Department, which has been led on a temporary basis by acting attorney general Matthew Whitaker since then-attorney general Jeff Sessions was ousted in November.
Barr previously served as attorney general from 1991 to 1993 under President George H.W. Bush and is highly respected in the conservative legal world. The Senate Judiciary Committee on Thursday voted to recommend his nomination to the full Senate. Acting Attorney General Matthew Whitaker is now filling the position.
Nadler said he might need the "threat" of the subpoena to get answers during the Friday session.
Making a clear commitment to releasing the special counsel's findings, said Vermont Sen.
The chair of the Senate Intelligence Committee told reporters this week that his panel has yet to see "anything" that would suggest the Trump campaign colluded with Russian officials during the 2016 presidential election.
Democrats and many Republicans have said they believe Mueller's final report should be fully released.
"This is particularly concerning, as nothing in existing law or regulations prevents the attorney general from sharing the report", Feinstein said Thursday.
Lawmakers have raised questions about a memo Barr wrote to Justice Department leaders questioning what he saw as the "fatally misconceived" theory of Trump obstructing justice that Mueller seemed to be exploring.
Dianne Feinstein, said last week that she is anxious that Barr won't be a check on the president who appointed him. Amy Klobuchar, a Minnesota Democrat, said Thursday. "I voted against Mr. Barr's nomination because I have little confidence in his willingness and ability to meet this challenge".
The Republican president has repeatedly criticized the investigation as a "witch hunt" and denies any collusion with Moscow.