It's a good thing Vice President-elect Joseph R. Biden Jr. will live in a sprawling mansion and not a condo because his family is about to get bigger - again.

Biden, a lifelong animal lover, says he will add a second dog when he moves to the Vice President's Residence in Washington next month.

"We're going to have more than one puppy," he said in an interview that will air today on the ABC News show This Week With George Stephanopoulous (6ABC, 10:30 a.m.).

Word that Biden will head to a shelter to adopt dog number two was cheered by animal-welfare advocates who were disappointed by his decision this month to buy a puppy from a breeder.

"It's so important that high-profile elected officials like the vice president set an example and demonstrate that the best source for dogs is your local animal shelter," said Wayne Pacelli, president of the Humane Society of the United States. "We are very grateful to the vice president-elect for making the humane choice."

Biden's purchase of a 6-week-old German shepherd from a Chester County breeder Dec. 6 touched off a national debate about pet-shopping.

Shelter and rescue advocates pointed to the millions of dogs euthanized in shelters each year and registered their unhappiness about Biden's decision in comments on Web sites across the Internet.

Biden told Stephanopoulos that he was partial to German shepherds, but that he had always had two "big dogs" as companions for each other.

"I've had German shepherds since I was a kid, and I've actually trained them and shown them in the past," Biden said in the interview. "So I wanted a German shepherd, and we're going to get a pound dog, which my wife wants, that is hopefully a golden" retriever.

Volunteers with Delaware Valley Golden Retriever Rescue in Reinholds, Lancaster County - which has placed two rescued dogs with Gov. Rendell - said they were thrilled with the news and hoped Biden would be interested in one of their dogs.

"There are plenty of dogs to rescue," said Judy Holmes, who has helped find homes for hundreds of unwanted dogs of all ages in the last 15 years.

It was unclear whether Biden had a particular shelter in mind, but if he chooses the rescue, he would have to go through its rigorous vetting process like everyone else.

"He still has to fill out an application," Holmes said. "We have a screening and matching process, and it works. Our return rate is very low."

And there's more to come on the presidential puppy trail. Next up: Which darling little dog will win the hearts of the Obama family?