Before starting the formal hearing proceedings, Sen. Arlen Specter, R-Pa., chairman of the Senate Judiciary Committee, allowed Alito to introduce his family attending the hearings. They included Alito's wife, two children, his sister, his in-laws and two cousins. Alito's 91-year-old mother was not able to attend.
Earlier Monday after a breakfast with Alito, President George Bush said Alito is eminently qualified for the job.
"I'm not the only person who feels that way -- the American Bar Association looked at his record, looked at his opinions, looked at his temperament, and came to the same conclusion, that he is well qualified to be a Supreme Court judge," Bush said.
The president also hoped the Senate would "bring dignity to the process and give this man a fair hearing and an up-or-down vote on the Senate floor."
The hearings, which may last four days or more, were expected to focus mainly on issues like privacy rights, abortion and domestic spying.
The New York Times reported the Democrats on the committee appeared lined up solidly against Alito.