Republican frontrunner Mitt Romney sidestepped a controversy over his Mormon faith at a summit of Christian conservatives Saturday a day after being attacked as "not a Christian."

Romney focused his speech to the Values Voter Summit mainly on President Barack Obama's economic and foreign policy, making no mention of his own Mormon religion and only a few references to God.

But the former Massachusetts governor appeared to allude to the previous day's controversy in a passage in which he called for decency and civility and warned: "Poisonous language does not advance our cause."

"The blessings of faith carry the responsibility of civil and respectful debate," Romney said. "The task before us to focus on the conservative beliefs and the values that unite us -- let no agenda, narrow our vision or drive us apart."

Friday, Texas pastor Robert Jeffress made headlines at the gathering when he put down the Mormon Church as a cult and said Romney "is not a Christian."

Jeffress made the remarks shortly after introducing Texas Governor Rick Perry, Romney's main rival, to the audience as "a genuine follower of Jesus Christ."

Christian conservatives are a powerful constituency of the Republican party and their support seen as crucial to winning the party's presidential nomination.

But Perry has slipped behind Romney in the polls, hurt by wobbly performances in recent debates and his support for in-state tuition for children of illegal immigrants.

Romney, meanwhile, stuck closely to his favorite campaign themes -- the troubled economy and Obama's foreign policy -- to polite applause from the Christian conservatives gathered here.

"Last week, the CEO of Coca-Cola said that the business environment in China is better than that here in the United States," he said. "China! If that is not an indictment of the Obama administration and of Washington, what is?"

"It's time to let a conservative businessman take the reins of government to make sure that America, not China, is the economic powerhouse of the world!" he said.

Romney also touched on some of the social issues that the Christian right most cares about, vowing to defend federal laws defining marriage as a union between a man and woman and bans on federal funding for abortion.

"We must continue to welcome faith into the public square and allow it to flourish," he said. "Our government should respect religious values, not silence them. We will always pledge our allegiance to a nation under God."