The Texas state education board's influential Christian conservative bloc was weakened Wednesday after one of its most prominent members lost his seat to a moderate Republican. Another reliably conservative seat was headed to a runoff.

Former board chairman Don McLeroy was handed a GOP primary defeat by lobbyist Thomas Ratliff. Ratliff conceded McLeroy never foisted his religious beliefs into textbooks, over which the 15-member State Board of Education has nationwide influence because Texas is one of the biggest clients for publishers. But Ratliff had criticized the 10-year board veteran for being too far right.

"Voters sent a clear message by rejecting the ringleader (McLeroy) of the faction that has repeatedly dragged our public schools into the nation's divisive culture wars over the past four years," said Kathy Miller, president of the Texas Freedom Network, which opposes Christian conservative initiatives. "Parents want a state board that focuses on educating their kids, not promoting divisive political and personal agendas."

Still, social conservatives claimed at least one victory as Ken Mercer of San Antonio successfully fended off a GOP challenge from Austin attorney Tim Tuggey. And conservative Brian Russell forced an April runoff with educator Marsha Farney in the race for the seat held by outgoing Christian conservative Cynthia Dunbar.

"I hope we can keep our conservative posture," Mercer said of the board. He'll face Democrat Rebecca Bell-Metereau in November.

"It's not anybody's ideology," he said. "It's just keeping the promises we made."

Primary results aside, the seven conservative Christians on the current board will have votes this spring on the adoption of a new social studies curriculum, a task that has been chock full of ideological flashpoints.

While early quibbles over how much prominence to give civil rights leaders such as Cesar Chavez and the inclusion of Christmas seem to have been smoothed over — neither will be removed from the standards — board members are crafting dozens of amendments to be raised for consideration before the first vote this month.

McLeroy, who believes the Earth is only 6,000 years old and that the Christian influences of the founding fathers are important to studying American history, lost his role as chairman last year following criticism of his outspoken views on creationism and support of teaching the weaknesses of evolutionary theory.

Dunbar drew the most attention in her single, four-year term by writing that public schools were a "subtly deceptive tool of perversion."

McLeroy, Dunbar and five other conservative Christians on the current board have secured majorities when picking up votes from one of three other Republicans or five Democrats.

One of the board's more moderate Republicans, Geraldine Miller, also lost her primary bid to keep the seat she has held since 1994. But little is known about her successful challenger, Dallas English teacher George Clayton, and it wasn't clear Wednesday where his votes might align. Clayton did not immediately return phone calls seeking comment.

Democrats Rene Nunez and Lawrence Allen Jr. are both running for re-election; Allen is unopposed. No Democrats filed to run for McLeroy's seat in November.

Tuesday's elections were the first since the board tackled evolution curriculum in 2008. During the heated debate that ultimately led lawmakers to oust McLeroy as chairman, the board decided Texas schools would no longer have to teach the "strengths and weaknesses" of evolution. Teachers still would be encouraged to consider "all sides" of scientific theories.