John Brennan won Senate confirmation Thursday to head the CIA after a late struggle that had more to do with presidential power to order drone strikes than with the nominee’s credentials to lead the spy agency.

The Senate voted 63-34 to give Brennan the top job at the nation’s spy agency. He will replace Michael Morrell, the acting CIA director since November.

The vote came after the Obama administration bowed to demands from Sen. Rand Paul, R-Ky., to specify limits on the president’s authority to order drone strikes against American citizens in the United States.

Paul declared he was satisfied with the administration’s statement, which said the president does not have the authority to use a drone to kill an American not engaged in combat on American soil.

Brennan’s credentials to head the CIA were scarcely mentioned in a final 24-hour stretch of political and constitutional drama surrounding his nomination.

Instead, Paul’s filibuster attracted widespread attention on Twitter and other social media, led the party to seek campaign contributions for the 2014 elections and prompted a parade of other tea party-backed senators to declare their support. Other Republicans were critical of the Kentucky Republican, harshly so.

The letter to Paul from Attorney General Eric Holder was brief:

“It has come to my attention that you have now asked an additional question: ‘Does the president have the authority to use a weaponized drone to kill an American not engaged in combat on American soil?'” Holder wrote.

“The answer to that question is no.”

Brennan has long appeared to hold enough votes to win confirmation.

But the letter marked the administration’s third concession in recent days in its attempt to bring the matter to a vote.

Earlier this week, responding to demands from lawmakers in both parties, the White House gave members of the Senate intelligence committee access to legal opinions justifying the use of lethal drone strikes against terror suspects. It also gave Republicans documents relating to last year’s deadly attack on the U.S. consulate in Benghazi, Libya.

Paul’s filibuster roiled the Republican party at the same time it got the attention of the White House.

Just hours after Paul ended his nearly 13-hour talkathon — and got an endorsement from minority leader and fellow Kentuckian Mitch McConnell — two senior Republicans on the Armed Services Committee dismissed Paul’s claims as unfounded and ridiculous and expressed support for Obama’s controversial drone program as the nation wages war against terrorism.

Both Sens. John McCain of Arizona and Lindsey Graham of South Carolina also challenged members of their own party.

“To my Republican colleagues, I don’t remember any of you coming down here suggesting that President Bush was going to kill anybody with a drone,” Graham said in remarks on the Senate floor.

McCain scoffed at Paul’s contention that the U.S. would have targeted actress Jane Fonda during her trip to Hanoi during the Vietnam War.

“I must say that the use of Jane Fonda’s name does evoke certain memories with me, and I must say that she is not my favorite American, but I also believe that, as odious as it was, Ms. Fonda acted within her constitutional rights,” said McCain, a prisoner of war in Vietnam for 5 1/2 years. “And to somehow say that someone who disagrees with American policy and even may demonstrate against it is somehow a member of an organization which makes that individual an enemy combatant is simply false. It is simply false.”

During the height of the long war, Fonda traveled to North Vietnam, visited with the enemy and was widely vilified.

After his remarks, Graham told reporters that he had planned to vote against Brennan’s nomination but now intends to support the nominee because the confirmation fight has become a referendum on the drone program.

Paul is pressing the administration for greater clarity on whether the Obama administration has the authority to use lethal force, such as a drone, against a suspected terrorist who is a U.S. citizen.

“Do you have the authority to kill Americans on American soil?” Paul summed up the question for reporters on Thursday. He said he had not received a response from the White House.

Hours after the filibuster, Republican leader McConnell said Paul deserves an answer.

“It simply doesn’t have that right, and the administration should just answer the question,” McConnell said. “There is no reason we cannot get this question answered today, and we should get this question answered today. Frankly, it should have been answered a long time ago.”

White House press secretary Jay Carney said White House officials had also been in touch with Paul’s office.

The Obama administration has said it has not conducted such operations inside U.S. borders nor does it intend to. Paul and backers said that wasn’t good enough. They wanted the White House to rule out the possibility of them happening altogether.

Paul’s performance, which centered on questions about the possible use of drones against targets in the United States, clearly energized a number of his GOP colleagues, who came to the floor in a show of support and to share in the speaking duties. And even as the night progressed, Paul appeared invigorated despite being on his feet for so long. Actual talking filibusters have become rare in the Senate, where the rules are typically used in procedural ways to block the other party’s agenda.

The National Republican Senatorial Committee used Paul’s stand to raise money for GOP candidates and said Thursday that they received donations “in the high five figures as of last tally.”

About a dozen of Paul’s colleagues who share his conservative views, many of them elected with strong support from tea party voters, came to the floor to take turns speaking for him and trading questions. McConnell congratulated Paul for his “tenacity and for his conviction,” and he called Brennan a “controversial nominee.”

Sen. Ted Cruz, R-Texas, read Twitter messages from people eager to “Stand With Rand.” The Twitterverse, said Cruz, is “blowing up.” And as the night went on, Cruz spoke for longer periods as Paul leaned against a desk across the floor. Cruz, an insurgent Republican with strong tea party backing, read passages from Shakespeare’s “Henry V” and lines from the 1970 movie “Patton,” starring George C. Scott.

Sen. Marco Rubio, R-Fla., made references to rappers Jay-Z and Wiz Khalifa. Rubio, a possible GOP presidential candidate in 2016, chided the White House for failing to respond to Paul. “It’s not a Republican question. It’s not a conservative question,” Rubio said. “It’s a constitutional question.”

(AP)