Continued from page 1

Rep. Darrell E. Issa, California Republican and chairman of the House oversight committee, said reports stating that wasn’t fully tested before it went live raises questions about whether the site can protect the sensitive data consumers are entering when they try to sign up for health plans.

Mr. Issa said he is seeking all correspondence between QSSI employees and the Obama administration. He said he had sent a letter to 11 contractors who helped build seeking documents, and had warned them that a failure to voluntarily turn materials over would result in a subpoena.

Ways and Means Democrats said Tuesday that the website glitches are problematic, but the law is working well in states that decided to set up their own insurance exchanges.

Their spirited defense of Mr. Obama’s reforms hit a dramatic high point when Rep. Bill Pascrell Jr., New Jersey Democrat, challenged Republicans to explain to the parents of children with pre-existing conditions that they plan to dismantle the law and its protections for those children.

Rep. John Lewis, Georgia Democrat and a civil-rights movement hero, said Republican opposition to the law reminded him of when senators from the South resisted a 1954 Supreme Court ruling to desegregate the schools.

“There have been a deliberate and systematic attempt on the part of the majority in the House and the minority in the Senate to make it impossible for all Americans to receive quality health care. And some of us will not stand for it,” he said, pounding on the dais. “We will stand up and fight for what is right, for what is fair and what is just. Health care is a right and not a privilege.”

Stephen Dinan contributed to this report.