As he moves to reclaim his place among the standard-bearers of the conservative movement, former House Majority Leader Tom DeLay (R-Texas) is roiling the leadership of one of its foremost organizations, the American Conservative Union.

DeLay was nominated to the board of the grass-roots group in December, prompting four longtime board members to resign in protest. He eventually joined the board in February.

In interviews and communications with ACU officials, the four board members who quit cited DeLay’s stewardship of spending increases and new entitlement programs during his tenure in House leadership as a betrayal of conservatives’ small-government agenda.

“He carried the water for some of the biggest government expansions in the history of the republic,” said Marc Rotterman, a North Carolina political strategist who quit the board after DeLay was nominated. “We looked at Tom DeLay to stop those kinds of bills, not to promote them. He was complicit.”

Rotterman and others pointed to the No Child Left Behind Act, which created the first-ever nationwide testing standard for public schools, the Medicare Part D prescription drug program and the explosion in federal earmarks as big-government measures that passed on DeLay’s watch.

The resignations were first reported in a column last week by Robert Novak.

ACU Chairman David Keene, who brokered DeLay’s involvement with the group, said the arrangement gives the Texas Republican a chance to make up for his performance in House leadership. “If you believe in redemption, he’s not there anymore,” Keene said. “His efforts on behalf of that team are no longer valid. He has great talent and solid beliefs, and he misapplied some of that talent when he held the job.”

A DeLay spokeswoman declined to comment for this story, but in an autobiography hitting bookshelves this week — “No Retreat, No Surrender” — DeLay offers a vigorous defense of his time atop the House GOP.

He lays the blame for recent policies that expand the scope of government at the doorstep of President Bush’s White House. “George W. Bush calls himself a ‘compassionate conservative,’ but he has expanded government to suit his purpose, especially in the area of education,” DeLay writes. “He may be compassionate, but he is certainly no conservative in the classic sense.”

Of his own performance, he writes, “I have tried throughout my political life to maintain a rigorous devotion to conservative principles.”

The ACU, founded in 1964, bills itself as the nation’s oldest and largest grass-roots conservative lobbying organization.

Unlike the array of single-issue groups on the right, the ACU advocates for a broad conservative agenda that stresses free markets, a hawkish defense policy and traditional values.

Its board is a mix of Republican donors and party operatives, in addition to more narrowly focused activists such as Grover Norquist of Americans for Tax Reform and Wayne LaPierre of the National Rifle Association.

Keene said DeLay’s talks with the ACU board began in the fall, before the elections that swept Republicans from power. DeLay resigned from the House in June 2006.

The initial plan was for DeLay to help the group ramp up its grass-roots network and in-town lobbying operation. The board would set the group’s legislative agenda, and DeLay would oversee its implementation, guiding the fundraising and lobbying strategy.

DeLay had secured $1 million in pledges for the effort, and Keene said he believed the former Majority Leader could quadruple the 20,000 grass-roots members the organization relies on to contact lawmakers on hot-button issues. In the fall, Keene said the board agreed to the concept of the arrangement, which also called for DeLay to join the ACU board.

When DeLay came to the board’s December meeting to present the plan, Keene introduced him. “Tom’s been on the dark side, but now we’re going to try to harness his talents to do the right thing,” Keene said he told the board.

The vote to approve the plan, including DeLay’s nomination, was unanimous, but some in the room, and others participating via conference call, said they felt strong-armed. “A lot of people thought it was improper to show up at a meeting before he was voted on,” said one board member, who asked not to be identified. “It did seem heavy-handed.”

Tom Pauken, a Dallas lawyer and former chairman of the Texas Republican Party, said he “just wasn’t supportive of the original plan.” Shortly after the meeting, he resigned from the board.

Later that month, however, as DeLay began to discuss the specifics with Keene, it became clear the arrangement wouldn’t work. DeLay wanted his operation to have more autonomy from the ACU than Keene was prepared to give.

Keene wrote to the board on Dec. 30 and explained the situation. “We have told him that while we may go our separate ways organizationally, we do want to work informally with him and his new organization as it develops just as we work with other groups comprising the broader movement of which we are all a part,” Keene wrote.

In the end, Rotterman, Pauken and two others — Craig Shirley of local firm Shirley & Banister Public Affairs and Robert Luddy, a North Carolina businessman — dropped off the board.

Shirley said he resigned the day after the December board meeting, largely to protest the DeLay proposal. Luddy did not return a call for comment, but Keene confirmed he quit over DeLay and his record on spending and entitlement programs.

DeLay and three others were voted onto the board last month.

One board member said some on the board remain skeptical of the DeLay arrangement. “I’m still around — for now. I think a lot of us are stepping back and waiting to see what happens next, and how the leadership deals with it.”

But Myron Mintz, another board member and Washington lawyer, said “there was no friction at all” over the DeLay decision and there is “nothing but harmony on the board.”

Opinion in the broader conservative community about DeLay appears to be split. Brad Dayspring, a spokesman for the House Republican Study Committee, which DeLay once chaired, said the Texas Republican was “extremely active in empowering it to where it stands today.”

“With respect to his conservative credentials, though from time to time there were disagreements, as there are bound to be with any member caucus and leadership, Mr. DeLay spoke at the conservative retreat in February and was very well received by the members in attendance,” he said.

Michael Franc, vice president of government relations at the Heritage Foundation, said DeLay remains in good stead with social conservatives and national security hawks. “But there are many rooms in the conservative mansion,” he said. “In the small-government room he has more work to do than in many others.”