National Taxpayers Union President John Berthoud, praised as "the happy warrior of fiscal conservatism," died Thursday. He was 47.

Mr. Berthoud, who had headed NTU since 1997, was found in his Arlington home Thursday morning by two NTU employees after he failed to show up for work, a spokesman for the organization said. He appeared to have died of natural causes, said Pete Sepp, vice president for communications at NTU.

"He shaped our entire culture and mission at NTU," Mr. Sepp said, reporting that NTU had received hundreds of e-mails and telephone calls not only from the Washington area but from around the country" sending condolences on Mr. Berthoud's passing.

Mr. Berthoud was a "great guy" who "stood up for taxpayers in a town that views taxpayers as chumps," said Grover Norquist, president of Americans for Tax Reform.

Mr. Berthoud served on the board of the American Conservative Union. "I am in shock and unable to gather any thoughts other than John was a wonderful friend and conservative colleague," said ACU Executive Vice President J. William Lauderback. "His absence from the conservative movement will be profoundly felt."

John Berlau, director of the Center for Entrepreneurship at the Competitive Enterprise Institute, noted that Mr. Berthoud worked closely with grassroots activists.

"John was the happy warrior of fiscal conservatism," said Mr. Berlau, who was a reporter for Insight magazine when he first met Mr. Berthoud. "He always made sure to take the message of low taxes and limited government beyond the Beltway. ... He made networking with state policy groups a priority and influenced others to follow in his footsteps in this area. John will be sorely missed, but his positive influence will be long felt."

Mr. Berthoud is survived by his mother and two brothers. Plans for a memorial service will be announced later, Mr. Sepp said.

Will update later with more details. Meanwhile, Mr. Berthoud's friends are memorializing him on his Facebook page.

-- Robert Stacy McCain, assistant national editor, The Washington Times