South Carolina Republican U.S. Sen. Jim DeMint is resigning his post (copy) (copy)

Former U.S. Sen. Jim DeMint, R-S.C. File/AP

WASHINGTON — A month after being abruptly ousted as president of the Heritage Foundation, former U.S. Sen. Jim DeMint said he felt "liberated."

The South Carolina Republican has quickly jumped from leading an academic conservative think tank to rejoining the grass-roots activist community — the same one that embraced him years ago while the GOP establishment chafed in almost equal measure.

"I can do more with a small group to support conservatives than I could at Heritage," DeMint told The Post and Courier on Tuesday. "I can do a whole lot more with the grass-roots for people who want to save the country."

DeMint has joined the Convention of States Project as a senior adviser.

Philosophically, the advocacy group lobbies for limited government and expanded states' rights. In practice, it's working to convince at least 34 state legislatures to assert their Article V authority in the U.S. Constitution and pass a resolution demanding the convening of a "convention of states."

In such a scenario, state legislatures, rather than Congress, would have the power to propose and vote on amendments to the Constitution relating to balancing the budget, reining in executive orders and imposing congressional term limits, among other things.

Thirty-eight states would still have to ratify the amendments for them to go into effect.

A fiscal hawk, DeMint advocated for a convention of states throughout his time at Heritage but was ultimately unable to get the organization to adopt a supportive stance.

"I was careful at Heritage not to impose my opinion on the researchers, but in this case I know what’s right. I’ve lived it," DeMint said. "No one can tell me there’s more risk in a states-amendment convention than there is in the status quo."

DeMint said it is still important to empower the elected officials who are "getting it right," at the state level and in Washington, D.C. Many of the conservatives elected to Congress in the 2010 tea party wave were actually DeMint recruits, and DeMint said they could be helpful to the cause.

"We’ve got to continue to support the people who are here and trying to make a difference," he said. "But on the big issues like fiscal restraint, that reach of the federal government into all areas of our lives, it's not going to happen unless the states pull that emergency break that the Constitution gives us."

DeMint faces an uphill battle in getting states on board with advocating for what would be termed a convention of states resolution, which even many conservatives strongly oppose.

It will likely be a challenge in his home state of South Carolina, too. There are currently 12 states that have passed convention of states resolutions; the Palmetto State is not one of them.

It is not for want of trying, said state Sen. Larry Grooms, R-Charleston, whose efforts pass a convention of states resolution have faltered in the most recent legislative sessions.

Grooms said he was hopeful DeMint would bring some "credibility" to the movement.

DeMint didn't promise he could win a victory for Grooms' resolution back in Columbia. But he did say he hoped to make the issue a part of the Republican platform in the 2018 midterm elections there. He said he planned to speak to state representatives up for reelection next year, along with any of the Republican candidates for governor.

"This should be a part of it," DeMint said. "It’s not enough to send representatives to Washington and then forget about them. It is the role of the state legislature to control the federal government. It’s been that way from the beginning."

If DeMint does manage to make a convention of states a focal point of 2018 races in South Carolina, that could add momentum to the movement. Jay Riestenberg, a spokesman for the government watchdog group Common Cause, conceded DeMint might be a formidable opponent in the organization's fight against the Convention of States Project.

"What I see DeMint’s value to them being, is opening doors to all these big Republican and conservative donors," Riestenberg said. "They are looking for more conservative donors to come to their crazy idea, and he’s the guy who can deliver on it."

If DeMint is able to mobilize grass-roots activists on the right to advance a convention of states resolution, Riestenberg said it would be up to grass-roots activists on the left to defeat it. Common Cause has successfully lobbied against convention of states resolutions elsewhere. 

U.S. Rep. Mark Sanford of Mount Pleasant and South Carolina's former Republican governor, said while he supported the concept, he wasn't optimistic it would ever come to fruition — or at least not with the help of his state.

"For conservatives, hope springs eternal, but keep in mind we live in a state where they won't even allow a public referendum," Sanford said. "We won't even allow that. This is the legislative body I fought for eight years of my life, which is 'we know what's best for y'all.'"

Emma Dumain is The Post and Courier's Washington correspondent. Reach her at 843-834-0419 and follow her @emma_dumain.