Peter Lehman Buttenwieser, 82, of Chestnut Hill, an educator, children's advocate, philanthropist, and major behind-the-scenes supporter of Democratic candidates and progressive causes, died Feb. 4, of acute myeloid leukemia at his home.

Though few Americans knew of him, Mr. Buttenwieser was a leading donor to the national Democratic Party and among the largest political contributors to the party in Pennsylvania.

He hosted more than 100 lunches for both Democratic challengers and incumbents, raising millions of dollars and making Philadelphia a sought-after destination for Democratic candidates. He was especially effective at raising money for Democratic candidates such as U.S. Sen. Bob Casey.

"Today, I mourn the loss of my dear friend Peter Buttenwieser," Casey said.  "A scion of a wealthy family, Peter chose to humbly use his privilege to support his community and our commonwealth.

"He spent every day of his life working to make the world a better place through his work, his philanthropy, and his political activism.  One of the earliest supporters of my first Senate campaign, Peter also became one of my most cherished friends.  I admired him and I will miss him."

When he believed in a cause or individual, Mr. Buttenwieser committed to it completely. He was one of the first to suggest that a U.S. senator named Barack Obama set his sights on the presidency, and he then supported Obama's 2008 presidential campaign.

Edward G. Rendell, mayor of Philadelphia from 1992 to 2000, said: "Peter Buttenwieser wasn't well-known to the public or the schoolchildren of Philadelphia, but I would say they had no better friend than Peter. He was heir to a fortune, but he became a teacher and practiced the art of advocacy, especially of those with like-minded views of education."

Mr. Buttenwieser was best-known as a funder of Democratic candidates, Rendell said, and became the "go-to person in Philadelphia for Democrats who believed in helping education." Mr. Buttenwieser was "a big factor in my run for governor," said Rendell who was Pennsylvania's top elected official from 2003 to 2011.

Most important, Rendell said, Mr. Buttenwieser never asked for anything in return for his support other than help with educational policy issues. "Most people give money because they want to ask for things that benefit themselves. Not Peter. He had strong values and he acted upon those values."

Mr. Buttenwieser was a consistent supporter of political change in the South, where his involvement ranged from trying to unseat U.S. Sen. Jesse Helms in 1990, to working with the NAACP in Mississippi to pass a 2015 state constitutional amendment fully funding public schools.

A generous philanthropist, Mr. Buttenwieser quietly targeted his giving to those he considered most in need. During the AIDS epidemic in the 1980s, he moved to fund AIDS clinics in rural communities where the disease carried a terrible stigma. He helped start AIDS hospices.

He served on the boards of Emily's List, to advance female candidates, and of the Brady Center to Prevent Gun Violence.

Born in New York City, he was the son of Benjamin J. and Helen Lehman Buttenwieser, and a descendant of one of New York City's illustrious Jewish families.  His grandfather, Joseph Buttenwieser, was a real estate mogul. His father was a philanthropist and investment banker; his mother a civil rights lawyer.

His mother's family owned the powerful Wall Street financial house Lehman Brothers.  She also was the niece of Herbert Lehman, who succeeded Franklin D. Roosevelt as New York's governor.

Mr. Buttenwieser graduated from the Putney School and what is now Columbia University and earned a master's degree in history from Harvard University and a doctorate in education from Columbia University's Teachers College.

He taught in New York City, Uganda, and North Carolina, and in 1970 founded the Durham Child Development Center, an innovative Philadelphia public school with child care and classes for teenage mothers with babies.

From 1980 to 2004, he served as an educational consultant, working closely with foundations to tackle the problems faced by poor and minority children in public schools across the country.

"He cared deeply about the future of children and our country, and found a variety of ways to help support a vision for both," his family said. "Much of the work he did was quiet and behind-the-scenes, and he felt most comfortable in mentorship roles."

One whom he mentored starting in 1993 was Frank P. Cervone, executive director of the nonprofit Support Center for Child Advocates in Philadelphia, which provides pro bono legal and social services for neglected or abused children.

"Peter graciously shared guidance and experience as school administrator, fund-raiser, philanthropist, and reformer," Cervone said. "He was a visionary of the best kind – eye always on the prize, persistent but gentle to make the point, filled with the spirit and the knowledge that justice would prevail, if only we all did our part."

Mr. Buttenwieser was married to Elizabeth Werthan. They had two daughters before divorcing. She survives.

In 1986, he married Terry Ann Marek, who had a daughter from a previous marriage. The couple enjoyed traveling and visiting their children and grandchildren. They loved attending the Philadelphia Orchestra and the movies. Their last two selections were Darkest Hour and The Post.

Among his greatest pleasures was tennis, which he played with a fierce competitiveness at Magarity Tennis Club in Flourtown. Head tennis pro and friend Steve Young said the two men played twice a week starting in 1994 and ending several months ago, when illness intervened.

"He was a kind, humble man," Young said. "He also cared about people. He asked questions and he listened. He was a great storyteller. He shared. It was the kind of relationship that was not one-sided by any means,

"He was like a father and a brother to me. I was lucky to be in same longitude and latitude at the same time as he was. I look at it, as not a loss, but a blessing."

Besides his wife, Mr. Buttenwieser, is survived by daughters Sarah Buttenwieser and Julie Suh; a stepdaughter Emily Edwards; 10 grandchildren; two brothers; and six nieces and nephews. A sister died earlier.

Services and burial will be private.

Memorial contributions can be made to Palliative Oncology at Penn Medicine, Penn Medicine Development, Attn: Kelly McBride, 3535 Market St., Suite 750, Philadelphia 19104, or online at  Checks should be made out to "Penn Medicine."