Richard J. Sestak, 54, of Springfield, Delaware County, brother of and campaign manager for former U.S. Rep. Joe Sestak, died of complications from cancer Wednesday, April 23, at the Hospital of the University of Pennsylvania.

Mr. Sestak grew up in Springfield, and graduated from Cardinal O'Hara High School, Villanova University, and Villanova University School of Law.

He started his law career in New York City, in the capital markets group of Price Waterhouse and went on to practice as a commercial litigator at Kittredge Donley in Philadelphia, and Baker & McKenzie, Brown & Winfield, and Ropes & Majeski in Los Angeles.

His family noted in a tribute that his work resulted in the first actuary malpractice verdict in the United States involving a public pension plan and the largest eminent domain verdict in California.

However, Mr. Sestak's love of politics - and his lifelong bond with his brother - drew him away from his law practice and into the political arena. Mr. Sestak took charge of his brother's first political campaign, and the result was an upset victory in 2007 over Curt Weldon, a 20-year incumbent, for the congressional seat of Pennsylvania's Seventh District.

"He had the heart of a warrior," said Joe Sestak, a retired Navy admiral. "It was always my pleasure riding into battle with him. He was the brains of it all, and there was no one I more value in my political career. I won because of him."

Mr. Sestak also coordinated Sestak's successful reelection campaign, served as the Southeastern Pennsylvania political and field director for Hillary Rodham Clinton's 2008 presidential campaign, and helped Joe Sestak win the Democratic senatorial primary against incumbent Arlen Specter in 2010.

Due to that success, Mr. Sestak was named one of the "top Democratic influencers" in Pennsylvania by Politics Magazine. Joe Sestak lost the election to current Republican Sen. Pat Toomey.

An accomplished athlete, Mr. Sestak loved football, baseball, and wrestling. He was a star triathlete and worked for the 1984 Los Angeles Olympic Organizing Committee.

He loved to garden and delighted his mother one year by landscaping her entire back yard.

"He brought so much joy to so many people," Joe Sestak said. "His enjoyment was enjoying others. At the end, a nurse broke down in tears talking about him. Even then, he was telling jokes and making others feel better."

In addition to his brother, Mr. Sestak is survived by sisters Kathleen, Barbara, Ann, Elizabeth, Margaret, and Patricia, and his mother, Kathleen.

A viewing will be held Sunday, April 27, at Ruffenach Funeral Home, 4900 Township Line Rd., Drexel Hill, from 6 to 8 p.m., and Monday, April 28, from 9:30 to 10:30 a.m. A Funeral Mass will follow at 11 a.m. at St. Kevin Church, 200 W. Sproul Road, Springfield. Burial will be at St. Peter and St. Paul Cemetery, Marple Township.

Donations may be made to the Sestak Scholarship Fund for students of academic excellence with financial need, c/o Cardinal O'Hara High School, 1701 S. Sproul Rd., Springfield, Pa., 19064.