1. SOUNDBITE (English) Sen. Joe Manchin, (D) West Virginia
"It's the first time I have had my phone light up last night right after six o'clock. My friends on both sides of the aisle were very impressed with this appointment. I think it basically shows we can rise above any cloud that's thrown on us in Washington."
2. SOUNDBITE (English) Sen. Ron Wyden, (D) Oregon
"Bob Mueller and I have certainly had differences of opinion, particularly with my concern with the government's authority to do surveillance on law abiding Americans, but I do consider him to be a professional and an honorable man."
3. SOUNDBITE (English) Sen. Dianne Feinstein, (D) California
"He's a very good attorney. He's a very diligent person. He's a wonderful man, and I think he will be a superior independent counsel."
4. SOUNDBITE (English) Sen. Pat Leahy, (D) Vermont
"You've got to have somebody of integrity, I think Bob Mueller does have that. I've known him for years. I worked with him both when I was chairman and as ranking member of the Judiciary Committee. I think Bob Mueller is a good choice."
5. SOUNDBITE (English) Richard Blumenthal, (D) Connecticut
"I'm very confident that Bob Mueller will do the right thing here, follow the evidence wherever it might lead. There is mounting evidence of obstruction of justice and impropriety and illegality that preceded this administration and may have continued while it's in power."
6. SOUNDBITE (English) Sen. Amy Klobuchar, (D) Minnesota
"Well, it's like a breath of fresh air has come into this week-long saga in that I think he is someone that has support on both sides of the aisle. You've heard barely a complaint about him which is quite unique. I got to work with him some because he was in the middle of an investigation of terrorist recruitment in Minnesota of people who were trying to join al-Shabab. I was really impressed with his work then, and I continue to be impressed by him."
Robert Mueller has been given sweeping power to investigate Russian interference in the 2016 US presidential campaign, an acknowledgment of growing public demands to place the politically charged inquiry into the hands of an outside investigator with bipartisan respect.
Senate Democrats reacted with virtually unanimous applause Thursday morning.
"Well, it's like a breath of fresh air has come into this week long saga in that I think he is someone that has support on both sides of the aisle," said Sen. Amy Klobuchar of Minnesota.
"You've got to have somebody of integrity, I think Bob Mueller does have that," said Sen. Patrick Leahy of Vermont.
The former FBI director has a broad mandate that could encompass any questionable actions of President Donald Trump's associates and possibly even the circumstances of last week's abrupt firing of James Comey.
As special counsel, Mueller will direct an FBI counterintelligence investigation examining whether Russia coordinated with Trump campaign associates to influence the election in his behalf.
He is entitled to a budget, can request new or additional staff and will have the same authority as high-ranking Justice Department lawyers, including the ability to prosecute any crimes he uncovers.