A shelter struggling to cope with the city's growing population of homeless people has resorted to using a lottery to determine which families get housing and which ones get turned away.

For the first time, Denver shelters say they're turning away large numbers of families with nowhere else to go. Rejected families are sleeping in cars, parks and abandoned buildings in dangerous neighborhoods.At Samaritan House, which can accommodate 20 families, applicants cut a deck of playing cards to win slots. The family with the highest card wins one of the shelter's 15 spaces.

"This is the worst it's ever been. We've never had to do anything like this before," said shelter social worker Sophie Rodriguez.

Families can stay at Samaritan for 30 days. Rooms become available every two or three days, said Mabel Risch, the shelter's family services coordinator. An average of about four applicants show up for the daily lottery, she said.

Homeless advocates blame the shortage of shelter space on the closure of a 25-family facility in March and, ironically, on Denver's improving economy.

"People hear about the new airport under construction and other development projects, and they expect jobs to be plentiful," said John Parvensky, director of the Colorado Coalition for the Homeless.