WASHINGTON (AP) - Catholic candidates from different generations will be facing off in the vice presidential debate.

Deal Hudson, author of "Issues for Catholic Voters, 2012 Edition," says Vice President Joe Biden comes from an older generation of Catholic politicians who have found a way to justify their support for legal abortion and same-sex marriage despite church teachings.

Hudson says Republican candidate Paul Ryan comes from a younger generation of "John Paul II" Catholics who have seen the church re-emphasize traditional teachings to rein in liberalizations triggered by the Second Vatican Council.

Hudson says the candidates' stark differences on abortion, marriage and the health care law's birth control mandate are almost certain to come up at the debate.