As an unofficial leader of the tea party movement, DeMint was considered among the most powerful members of Congress. He cultivated a set of loyal followers -- and bitter detractors -- by backing conservative Senate candidates that he felt would be allies in confronting less hardline Republican leaders. A nod of support from his Senate Conservative Fund, which raised over $16 million in the most recent cycle alone, could put a previously obscure candidate on the national map immediately. Some of his bolder endorsements, like Sen. Marco Rubio (R-FL) and Rand Paul (R-KY), are now considered some of the party's brightest stars. Others, like Christine O'Donnell, became some of the party's biggest disasters.
DeMint embodied the "party of no" label the GOP earned over the last four years, frequently leading filibusters to stymie President Obama's agenda and often threatening to scuttle deals reached between the White House and Republican leaders. During the 2009 health care debate, he famously described the Affordable Care Act as Obama's "Waterloo," saying its defeat would "break him."
Sen. Mitch McConnell (R-KY), who clashed with DeMint at times, praised his "uncompromising service" in a statement released after news broke of DeMint's decision to step down.
"Jim helped provide a powerful voice for conservative ideals in a town where those principles are too often hidden beneath business as usual," McConnell said.
The Heritage Foundation appears to be a good fit for DeMint's style. Some of its staffers have clashed with Republican leaders in recent days, leading the charge against Speaker Boehner's proposals to raise revenue as part of a fiscal cliff deal and hosting speaking engagements for conservative members of Congress who were stripped of their committee assignments.
But far from being a bomb-throwing outfit on the fringe of the Republican Party, the generously funded Heritage Foundation sits at the core of modern Republican Party in Washington. McConnell's wife, Elaine Chao, a labor secretary under George W. Bush, is a distinguished fellow at Heritage, whose headquarters is just a couple of blocks from the Senate side of the Capitol complex.
It also presents a likely boost in compensation: DeMint makes $175,000 in salary as Senator, but outgoing Heritage president Edwin Feulner took home about $1,100,000 in 2010 according to the group's public tax forms. DeMint is one of the least wealthy members of the Senate, reporting a net worth of $65,000 last year.
The group parallels DeMint's -- and the GOP's -- rightward shift in the Obama era. As Slate's Dave Weigel noted on Thursday, DeMint supported Mitt Romney's campaign in 2007, citing his mandate-based health care law. Romney in turn adapted his law from mandate-based proposals backed by the Heritage Foundation. By 2009, all three were leading opponents of Obama's mandate-based health care reforms.
"Jim DeMint understands that conservative principles and values advance the interests of all Americans--regardless of age, gender, wealth or race," Feulner said in a statement. "He is firmly committed Heritage's immutable mission: to build an America where freedom, opportunity, prosperity and civil society flourish."