By Shawn Zeller, CQ Staff

President Obama is on his way to setting a modern record for the speed at which his initial nominees for top agency posts are winning confirmation by the Senate, outpacing every other president going back at least to Ronald Reagan. But in the world of political appointments, that’s not saying much.

A tally by the White House Transition Project, a group of academics funded by the Pew Charitable Trusts, found that after 160 days in office, a mark that came during the July Fourth congressional recess, less than 40 percent of the most plum political jobs had been filled and that Obama had sent nomination papers to the Senate for slightly more than half of the jobs.

The Defense Department, for instance, is still without the undersecretary who manages its workforce. The Homeland Security Department as yet has no one to run the Transportation Security Administration, which handles screening at the nation’s airports. At the Treasury Department, where Secretary Timothy F. Geithner wrestles with the recession, less than a quarter of the positions requiring confirmation have been filled.

“When you have positions in the executive branch that are at the center of the policy making for the president’s agenda, and they are delayed by six, nine or 12 months, that’s a serious problem,” says John M. Kamensky, a senior fellow at the IBM Center for the Business of Government who was deputy director of Vice President Al Gore’s National Partnership for Reinventing Government in the 1990s.

But, Kamensky notes, efforts to speed the process have met with repeated failure. “Each of the different Senate committees with jurisdiction is reluctant to give up its autonomy,” he says.

Politics play as much a role as a nominee’s competence.

Republican senators, for instance, held up Obama’s nominee to head the Census Bureau, University of Michigan survey researcher Robert M. Groves, out of concern he would favor statistical sampling in the 2010 Census as a way to better account for minorities and the poor. A showdown vote will come this week.

This spring, Republicans also delayed the confirmation of former Yale Law School Dean Harold Hongju Koh as the State Department’s legal adviser to protest his support for a more international approach to resolving disputes.

And Republicans aren’t the only ones willing to hold nominees hostage: For several weeks Democratic Sen. Robert Menendez of New Jersey held up the confirmation of Obama science adviser John P. Holdren, a former Harvard professor, reportedly to send a message that he will not tolerate overtures to Cuba by the administration.

Despite such delays, according to the White House Transition Project’s research, the White House is spending more time vetting potential nominees and picking people for each job (53 days on average) than the Senate is spending reviewing nominees before granting its consent (37 days).

Efforts to expedite the process face long odds, says G. Calvin Mackenzie, a government professor at Colby College who has served on several blue ribbon panels over the years with just that goal in mind. “I retired in frustration,” he says. “I don’t think anyone is satisfied, but there’s no motivation to change. Whatever individual senators think in grandiose political science terms about fixing the process, they want to maintain every opportunity to slow down an appointment.”