He added: "To whatever degree people are trying to view Roberts as an ideologue whose first instinct is to take his worldview and impose it on whatever decision he's taking -- this cuts against it."
The result, Ornstein said, is that the controversy is likely to help Roberts win more support from moderates.
Roberts' involvement in the case means he can "put himself in someone else's shoes," Ornstein said. "That is something that has distinguished the more careful and modest justices from the more expansive, wide-ranging and reckless ones."
Many conservatives said they wanted to know more about why Roberts agreed to help in the case and whether he did so out of conviction or courtesy to a colleague.
Jay Sekulow, who is helping the administration promote Roberts' nomination, said he had spent time Thursday explaining to concerned conservatives that lawyers often consulted with other lawyers on cases, regardless of their personal convictions.
"A lot of people are commenting who don't know about Supreme Court practice. There's a high degree of collegiality," said Sekulow, who is chief counsel for the conservative American Center for Law and Justice.
Walter A. Smith Jr., the partner at Hogan & Hartson who ran the firm's pro bono program, said that Roberts took part in the firm's initial meeting to consider accepting the case and that his participation, as in all of the firm's pro bono cases, was voluntary.
"Anyone who didn't want to work on a case for whatever matter, they didn't have to," Smith said. "He was in on the takeoff and he was in on the landing and was helpful in both."
From a lawyer's point of view, Smith said, the Colorado case was more about equal protection than about gay rights.
He said the crucial issue for Roberts -- and eventually for the Supreme Court -- was whether the Colorado initiative took away ordinary rights and legal protections from a disadvantaged group, whether a sexual, racial or social minority.
"From a lawyer's point of view, it presented an equal protection question," Smith said. "Does such a law violate the equal protection clause of the Constitution? To that extent, it was not a gay rights issue."
