Tim Goeglein admitted he had copied much of an essay that appeared in a Dartmouth College publication about a decade ago, and claimed the writing as his own in a column for the News-Sentinel, The (Fort Wayne) Journal Gazette reported Friday.

Goeglein made the admission in an e-mail to The Journal Gazette Friday. "I am entirely at fault," he said. "It was wrong of me. There are no excuses."

Goeglein acknowledged he had plagiarized in other guest columns as well, The Journal Gazette said.

White House Press Secretary Dana Perino issued a statement saying President George W. Bush was "disappointed to learn of the matter and he was saddened for Tim and his family."

Goeglein joined the White House staff in 2001, and was responsible for maintaining relationships between the administration and various religious and conservative groups.

The White House said Goeglein turned in his resignation Friday.

The News-Sentinel said it found sections copied and used without attribution in 20 of 38 Goeglein columns it had published during the past eight years, The Journal Gazette said.