Conservative leader Paul Weyrich died Thursday.

A co-founder and the first president of the conservative think tank Heritage Foundation Weyrich, 66, was also chairman and CEO of the Free Congress Foundation. The Heritage Foundation issued a two-line statement that did not state the cause of death but said Weyrich died around 1 a.m. ET.

The Republican National Committee issued a statement extending its condolences to Weyrich's friends and family. 

"Paul's service to America has embodied and further advanced the Republican Party's core values of limited government, lower taxes and individual responsibility. We are saddened by the passing of Paul Weyrich, but we know that his contributions will continue to resonate for generations," said RNC Chairman Mike Duncan.

Outgoing Republican Minority Whip Roy Blunt also issued a statement. 

"No matter the challenges Paul was facing in his personal life, he was always acutely aware of the challenges facing our nation and devoted his entire life to strengthening our country. His ability to persuade without berating, and teach without demeaning are lessons that would serve many on both sides of the aisle well," Blunt said.

Lee Edwards, a Heritage Foundation scholar and a friend, said Weyrich had suffered from ill health in recent years and had both legs amputated.

"He was a dedicated conservative and patriot, an excellent strategist," Edwards said. "He had a very sharp sense of humor , which he employed at all times."

Weyrich, who lived in northern Virginia, was one of three founders of the Moral Majority, and later had a hand in creating the Christian Coalition.

Weyrich got his start as a reporter in Milwaukee, and came to Washington in 1967 as press secretary to Sen. Gordon Allott, R-Colo. 

Six year later, he founded the Heritage Foundation, and the next year the Free Congress Foundation. At a 1979 gathering of religious leaders, Weyrich talked of a "moral majority" in the country. The name stuck. Over the next decade, the group led by the Rev. Jerry Falwell energized the conservative movement as a political force.

By the late 1990s, Weyrich was lamenting that "I no longer believe that there is a moral majority." If there were, he said, "Bill Clinton would have been driven out of office months ago."

Tony Perkins, president of the Family Research Council, said Weyrich "didn't over-intellectualize about Christians 'jumping into the fray.' He recognized early that the fray had jumped onto us."

As recently as Wednesday, Weyrich had published an article on the Minnesota Senate recount that appeared on the Free Congress Foundation Web site. 

He is survived by his wife, Joyce, five children and several grandchildren. 

The Associated Press contributed to this report.