On a recent Tuesday afternoon, Sam Brownback, the former governor of Kansas and a champion of socially conservative causes, asked a small crowd of his fellow Christian voters if they were feeling discouraged.

Inside this church in Grapevine, Texas, nearly every hand shot up.

The response might seem mystifying: These voters had won huge victories, most notably in overturning Roe v. Wade, which had guaranteed the constitutional right to abortion.

And Mr. Brownback sat alongside a former football coach whose victory in another Supreme Court decision allowing prayer on the field symbolized the court’s decisive swing in their favor.

But with the presidential election closing in, hope suddenly felt thin. Powerful efforts to “suffocate” their values seemed to be everywhere, Mr. Brownback said to widespread agreement.

He tried to offer reassurance. He recounted the biblical story of Gideon, who triumphed in battle against a vast army with only 300 men by his side.

“God never needs a majority,” he said. “All he needs is a faithful remnant.”

As opposition to their social agenda grows, particularly on abortion, many conservative Christians are experiencing whiplash as they grapple with an uncertain future.