Republican Party leaders have been quick to condemn Donald Trump’s proposal to bar all Muslims from entering the United States, but the idea is not anathema to a group of Senate conservatives that includes his presidential rival, Ted Cruz.

On Thursday afternoon, Democratic Senator Patrick Leahy of Vermont offered an amendment to a nuclear terrorism bill in the Judiciary Committee stating that it was “the sense of the Senate that the United States must not bar individuals from entering into the United States based on their religion, as such action would be contrary to the fundamental principles on which this nation was founded.”

Simple enough, it would seem. Yet Cruz and three other Republicans on the committee—Senators Jeff Sessions of Alabama, David Vitter of Louisiana, and Thom Tillis of North Carolina—all voted against it. The seven other Republicans on the panel, including long-shot presidential hopeful Lindsey Graham, supported the amendment. Cruz was not present for the debate and voted by proxy, which is allowed only in committee votes in the Senate.

Cruz’s Senate spokesman, Phil Novak, said the resolution was “nothing more than a political stunt” that was unrelated to the underlying legislation. “A nuclear terrorism bill is not the place for political games," Novak wrote in an email, “which is why after voting against Senator Leahy’s amendment, Senator Cruz voted for the nuclear terrorism bill to protect Americans against this grave threat.” Novak didn’t respond when pressed on whether Cruz believed that a religious test for entering the U.S. was appropriate.

Cruz’s vote is less surprising when considering that of all of Trump’s major rivals, he has expressed the least alarm at his proposal to temporarily ban Muslim entry. “Well, that is not my policy,” he told reporters initially before touting his own more limited plan to place a three-year moratorium on resettling refugees from countries where ISIS or al Qaeda have a presence. And as he has risen in the polls, Cruz has been reluctant to criticize Trump at all and risk alienating voters he hopes to gain if Trump eventually fades. After The New York Times reported Thursday that Cruz had questioned Trump’s “judgment” at a private fundraiser, the Cruz campaign issued a statement calling the story “misleading.”

On Capitol Hill, the most extensive argument against Leahy’s amendment came from Sessions, who for years has taken the most hardline positions in the Senate against any expansion in legal immigration or legal status for undocumented immigrants. In a lengthy statement, Sessions said that choosing who can come to the United States is “by definition, an exclusionary process” and distinct from the constitutional protections that apply to citizens. “The adoption of the Leahy Amendment would constitute a transformation of our immigration system, Sessions said. “In effect, it is a move toward the ratification of the idea that global migration is a ‘human right,’ and a civil right, and that these so-called ‘immigrants’ rights’ must be supreme to the rights of sovereign nations to determine who can and cannot enter their borders.”

Four of 11 Republican senators on a committee panel may be a tiny—if influential—sample, but the vote seems to reflect the sentiments of a sizable portion of the party’s base. Polls released on Thursday found anywhere from 42 percent to 65 percent of Republican primary voters agreed with Trump’s proposal to block Muslims. (Whether they are agreeing with the policy or just agreeing with Trump is another matter, as my colleague David Graham ponders.) If nothing else, the four no votes on what a month ago would have seemed a noncontroversial statement of principle is yet more evidence of the yawning gap between the GOP leadership and a much more restive conservative base.