Roberts won the endorsement of all of the committee's 10 Republicans and three of its eight Democrats.
The panel's ranking Democrat, Patrick Leahy of Vermont, said Wednesday he would vote in favor of the nominee. Democratic Sens. Herb Kohl and Russ Feingold, both from Wisconsin, followed suit.
"I take him at his word that he will steer the court to serve as an appropriate check on potential abuses of presidential power," Leahy said on Thursday.
Throughout Roberts' confirmation hearings, Republicans hailed the federal appellate judge and former attorney as a dispassionate "umpire" who would decide cases based solely on the law. Republicans argued that Roberts' professional qualifications and personal character mattered most, not his stance on issues. Roberts himself asserted that decisions on political issues should be handled by legislatures not judges.
"I applaud my colleagues who were able to put Judge Roberts' qualifications above the ideological litmus tests of outside groups," said Texas Republican Sen. John Cornyn. "He is, by their own accounts, one of the most impressive and well-qualified nominees ever nominated to the Supreme Court. So I must also ask those who are bound and determined to vote against this nominee, is there any nominee who shares this president's views for whom they could vote? I fear the answer to that is 'no.'"
Sen. Dianne Feinstein, D-Calif., along with Sens. Edward Kennedy, D-Mass., Joseph Biden, D-Del., Charles Schumer, D-N.Y., and Dick Durbin, D-Ill., voted to oppose confirmation.
Feinstein told reporters that Roberts' resistance to answering most questions about his political or ideological opinions on key issues such as abortion during his confirmation hearings left senators with too little information about how he would serve as chief justice. Feinstein is a staunch supporter of abortion rights.
"I knew as little about what Judge Roberts really thought about issues after the hearings as I did before the hearing. This makes it very hard for me," she said. "I cannot in good conscience cast a 'yea' vote."
In a statement Biden said, "I believe this is a very close call -- a very close call. I respect those of you who will vote for him, and I respect those of you who are voting no, because it is so close." In the end Biden said he did not believe Roberts would protect "fundamental constitutional rights."
Other Democrats echoed Biden's concerns about rights, especially those connected to social movements for change in U.S. history, which Democrats hailed throughout the Roberts' confirmation hearings as "progress" that cannot be turned back.
"Based on the record available, there is insufficient evidence to conclude that Judge Roberts' view of the rule of law would include as paramount the protection of basic rights," Kennedy said in a statement. "The values and perspectives displayed over and over again in his record cast doubt on his view of voting rights, women's rights, civil rights, and disability rights."
The full Senate is scheduled to start debating Roberts' nomination on Sept. 26. He is expected to pass by a wide margin.
The Supreme Court's next session begins Oct. 3.