WASHINGTON (AP) – President Barack Obama is appointing a key union activist as senior adviser to Labor Secretary Hilda Solis.

Mary Beth Maxwell’s appointment is seen as another sign of the influence that organized labor wields in the Obama administration.

Maxwell spent the past five years as executive director of American Rights at Work, a nonprofit group pushing for passage of a bill to make it easier to form unions.

At Labor, Maxwell will serve as a liaison to the White House Task Force on Middle Class Working Families, a group charged with improving labor standards.

Democratic leaders in Congress hope to bring some version of the Employee Free Choice Act to a vote this summer. Democrats are trying to rally enough votes to overcome an expected GOP filibuster.