DES MOINES, May 11 — Mitt Romney expanded on his belief in evolution in an interview earlier this week, staking out a position that could put him at odds with some conservative Christians, a key voting bloc he is courting.

Mr. Romney, a devout Mormon, surprised some observers when he was not among those Republican candidates who raised their hands last week when asked at the Republican presidential debate if they did not believe in evolution. (Senator Sam Brownback, former Gov. Mike Huckabee and Representative Tom Tancredo said they did not.)

“I believe that God designed the universe and created the universe,” Mr. Romney said in an interview this week. “And I believe evolution is most likely the process he used to create the human body.”

He was asked: Is that intelligent design?

“I’m not exactly sure what is meant by intelligent design,” he said. “But I believe God is intelligent and I believe he designed the creation. And I believe he used the process of evolution to create the human body.”

While governor of Massachusetts, Mr. Romney opposed the teaching of intelligent design in science classes.

“In my opinion, the science class is where to teach evolution, or if there are other scientific thoughts that need to be discussed,” he said. “If we’re going to talk about more philosophical matters, like why it was created, and was there an intelligent designer behind it, that’s for the religion class or philosophy class or social studies

class.”

Intelligent design is typically defined as the claim that examination of nature points to the work of an intelligent designer, as opposed to the utterly random, naturalistic processes that are taught as part of evolutionary theory. Critics have called intelligent design a thinly disguised version of creationism, which takes a literal approach to the creation account in Genesis, that the earth was created in six days and is less than 10,000 years old.

Mr. Romney said he was asked about his belief in evolution when he was interviewed by faculty members for highest honors designations before his graduation from Brigham Young University.

He told his interviewers that he did not believe there was a “conflict between true science and true religion,” he said.

“True science and true religion are on exactly the same page,” he said. “they may come from different angles, but they reach the same conclusion. I’ve never found a conflict between the science of evolution and the belief that God created the universe. He uses scientific tools to do his work.”

The Church of Jesus Christ Latter-day Saints has no definitive position on evolution, and church leaders have disagreed on the issue over the years.

Mr. Romney said his answer was satisfactory to faculty members. “They teach evolution at B.Y.U.,” he said.