WASHINGTON – Andrew Card should be a fish out of water in the Bush White House.

He favors abortion rights, he supported President Clinton’s health-care plan and he’s won past endorsements from Democratic Massachusetts Sens. Edward Kennedy and John Kerry. But his skills as White House chief of staff have become more valuable than ever as President Bush heads into a second term.

It’s no accident that the first personnel decision Bush made after he was re-elected was to keep Card at the center of his inner circle. While largely invisible to the public, Card wields considerable influence as a gatekeeper and confidant to Bush, a referee in administration turf fights and a traffic cop for the flow of information.

When presidential scholars and political insiders marvel at the discipline in the Bush White House, they’re really paying tribute to Card.

“He’s probably run one of the tightest ships ever,” said David Cohen, a political science professor at the University of Akron and an expert on the role of White House chiefs of staff. “It’s not a surprise that the president asked him back. He’s made a big difference in this White House.”

Card’s steady hand has become even more important as Bush juggles personnel changes for his second term.

Card’s friends had expected him to join the second-term exodus, if for no other reason than sheer exhaustion. His job is considered one of the toughest in Washington, with an average tenure of about two years.

“It’s 24-7. There are no breaks. Maybe Sunday afternoon there are a few hours when you can sit down and try to relax, but it’s constant,” said Leon Panetta, who served three years as Clinton’s chief of staff. “You’re usually the first person the president is going to call if he’s mad or upset or has something he doesn’t like.”

Card, 57, knew exactly what he was getting into.

He’s an old Washington hand, serving as President Reagan’s liaison to the nation’s governors in the early 1980s, and as an assistant to Chief of Staff John Sununu under President George H.W. Bush, the current president’s father. In 1992, the elder Bush named Card secretary of transportation.

Card came to Washington after a moderately successful political career in his native Massachusetts. After earning an engineering degree from the University of South Carolina, he was elected to the Massachusetts legislature in 1974. He earned a reputation as an earnest reformer during his four terms in office, but failed to win his party’s nomination in a 1982 campaign for governor.

Card has a home in Poland and made several visits to Maine during the campaign, stumping hard for President Bush’s re-election.

He was, like most Northeastern Republicans at the time, a liberal by the standards of today’s Republican Party.

“He’s not an ideologue,” said Philip Johnston, the chairman of the Massachusetts Democratic Party and a friend of Card’s since their days in the legislature.

Card, whose wife, Kathleene, is an Episcopal minister, has three children and four grandchildren. The job’s demands aren’t enough to keep him from knowing how his alma mater’s football team is doing. In an Internet chat during the campaign, Card told a fellow alum, “Go, Gamecocks. They are off to a great start this year – 4 and 1.”

Card’s ties to the Bush family go back to 1980, when he backed George H.W. Bush in his unsuccessful first campaign for president. Johnston said Card went with Bush because he considered Reagan “too right-wing.”

Card, who has a reputation as one of the nicest people in Washington, has admirers in both parties. Kennedy and Kerry urged their fellow senators to confirm him for the Transportation Department job.

“He is skilled at the art of compromise and working out solutions to very complex problems,” Kerry told the Senate Commerce Committee at the time. In an aside that now has an ironic twist, Kerry joked that Card knew “how to lose gracefully and repeatedly” from his experience as a Republican in Democratic Massachusetts.

Card, who speaks with a thick Massachusetts accent, says he offers comic relief to an often-stressed president. Last Christmas, Card appeared in a Webcast with Barney, the Bushes’ dog. It opens with him grabbing Barney by the head and asking him to help trim the tree. He said: “I need your cooperation. … The president is counting on you.”

Both are comments he’s accustomed to making.

His low-key style and willingness to stay in the background make him a nice fit for Bush, who demands loyalty and deference.

“My job is to be a staffer. … I’m not the president-in-waiting,” Card said in an interview with Knight Ridder six months into the job. “I’m not the prime minister.”

For all Card’s success with message management and discipline within the administration, some question why he seemed unable or unwilling to mediate foreign policy squabbles between Secretary of State Colin Powell and Defense Secretary Donald H. Rumsfeld. His defenders suggest that National Security Adviser Condoleezza Rice should have taken on that job.

Others speculate that Bush wanted to send conflicting signals to maintain flexibility.

In any case, Card has largely quieted skeptics who said he was too nice for a job that sometimes required him to be a presidential enforcer.

“He’s about getting the job done,” Republican Party Chairman Ed Gillespie said. “He knocks heads in a nice way, but he’ll knock your head. The first screw-up will be accepted. The second will not.”