The field of religious advocacy has mushroomed on Capitol Hill in recent decades, a new survey shows, with the number of groups growing fivefold since 1970 and hundreds of millions spent each year to influence issues from school vouchers and immigration to the right of women overseas to have abortions.

The report, released Monday by the Pew Forum on Religious and Public Life, appears to be the most extensive research ever done on D.C.-based lobbyists and advocates on faith matters. It documents the widening range of domestic and foreign issues religious groups push and fight and shows the entrance in recent years of religious minority groups, such as Muslims, Sikhs and secular organizations, into the field.