The Philadelphia Museum of Art will announce Wednesday that it has successfully completed a five-year, $54 million campaign to endow 29 staff positions across the full range of museum departments, from painting and sculpture to digital technology.

The campaign began in 2008 when H.F. "Gerry" Lenfest, then chairman of the museum's board of trustees, and his wife, Marguerite, offered a $27 million grant and challenged donors to match it, million for million, for the right to endow and name the positions. (Lenfest is a co-owner of The Inquirer.)

The Lenfests' commitment of $27 million is the largest single financial gift ever made to the museum, and makes them its largest financial donors, with more than $100 million to date.

Timothy Rub, the museum's director and CEO, said Tuesday of the challenge, "It was formidable when established, right at the very start of the recession when there was a tremendous amount of uncertainty in the world." At that time, institutions were losing endowment value and laying off employees.

The challenge now has been met by 27 donors, 19 of whom are making first-time gifts at the million-dollar level.

"Structuring it as a challenge was an incredibly important strategic decision to make," said Rub. "They put some substance behind that goal."

First to respond were museum trustee Keith Sachs and his wife, art historian Kathy Sachs. They endowed the position of Carlos Basualdo, whose title is now the Keith L. and Katherine Sachs Senior Curator of Contemporary Art.

In a statement accompanying the announcement that the challenge has been met, current board chairman Constance H. Williams calls the grant "a galvanizing act that addresses the heart of our needs. . . . This represents a milestone in the history of this institution."

The museum's endowment now stands at $408 million, including $32 million of the Lenfest challenge money; the rest will roll in over the next five years. The campaign actually surpassed the $54 million goal, topping out at $55.5 million.

That $408 million is well below the endowments of New York's Metropolitan Museum of Art (which fluctuates between $2 billion and $3 billion) and of the Art Institute of Chicago (more than $800 million). But the museum is far better off than it was in the second half of 2008, when its endowment tumbled from $346 million to $256 million, forcing program cuts, exhibition delays, and the elimination of 30 jobs.

The drive brings the museum's total number of endowed positions to 50, above or on par with its peer institutions.

Having "endowed positions accomplishes two things," Rub said. "It honors people who have been here . . . and what they've accomplished and also makes it easier for us to attract really first-rate curatorial staff. Having an endowed position is . . . quite comforting."

The success of the campaign may also reflect stirring optimism about the economy. "The continued renewal of the economy has given donors and supporters much greater confidence about making these commitments," said Rub.

The list of endowed positions illuminates a cross-section of the museum's priorities, from art to education to publishing to outreach. As at many museums, there are curators for various periods and types of painting and sculpture, for prints and photography, for costumes and textiles and installation design. But there are also curators dedicated solely to Chinese, Korean, Indian, and Himalayan art, which Rub called "fantastic to have." And one of the endowed positions is that of senior scientist, who he said does "analytic studies into the materials of which certain objects are made."