South Dakota ? Billionaire banker T. Denny Sanford says he wants to die broke.

And he says Kelby Krabbenhoft, president and CEO of Sioux Valley Hospitals & Health Systems, “is certainly doing the best job he can to make it happen.”

Krabbenhoft pursued Sanford by telling him of the hospital’s dream to transform the facility into a major research institution for children’s health. Sanford donated $400 million, and the hospital promised to rename the institution after him – Sanford Health.

The hospital began in 1894 and has grown to become the largest employer in the region, with 12,000 employees, 340 physicians, 115 clinics and 24 hospitals.

The $400 million will go toward several projects that will bear Sanford’s name and expand the health system beyond its current patient base in South Dakota, Minnesota, Iowa and Nebraska. They include building five pediatric clinics tied to the new children’s hospital in Sioux Falls that will bear his name and are scheduled to open in 2009.

Sanford, 71, has a net worth of roughly $2.5 billion. He made his fortune as the owner of First Premier Bank and Premier Bankcard – among the nation’s leading credit card providers.