A constitutional amendment that would return official prayer to public schools and permit government funding of religious activity passed an important test Wednesday, clearing the way for a historic vote by the House this spring.

The House Judiciary Committee approved the Republican-sponsored amendment 16 to 11 on a party line vote. Republican leaders have promised religious conservatives a vote by the House in late April or early May.It has been 27 years since the House last voted on a school prayer constitutional amendment, and never on one so broadly worded as the amendment authored by Rep. Ernest Istook, R-Okla.

It is unlikely the amendment will be able to gain the required two-thirds majority, but supporters have promised to wage a fierce battle for passage. Televangelist Pat Robertson's Christian Coalition is planning a multimillion-dollar television ad campaign targeting lawmakers in closely contested districts.

Even if the amendment fails, the coalition is expected to cite the vote in the approximately 45 million voter guides it distributes to church-goers just before Election Day.

The floor vote would fulfill a promise that House Speaker Newt Gingrich, R-Ga., made to religious conservatives three years ago. The delay has been partly attributable to infighting among conservatives over the amendment's wording and partly to the reluctance of GOP leaders to tackle the emotionally charged issue.

Most legal and religious authorities agree that there already is a significant amount of religious expression permitted in public schools under existing Supreme Court interpretations of the "free exercise" and "establishment" of religion clauses of the First Amendment.

Students are legally permitted to pray before and after class, say grace over meals, read Bibles and express their religious views to other students so long as they are not disruptive. Groups of students may meet to pray on school property, such as "see you at the flagpole" prayer groups. And Bible clubs have the same right to use school property and announce their meetings in student newspapers as other clubs, although teachers are not permitted to participate in an official capacity.

In general, the court has forbidden religious activity that can be construed as coercive and disruptive or that makes students captive audiences for proselytizing.

However, supporters of the amendment say the court has gone too far, robbing government of all but the most innocuous religious references and sometimes making government outright hostile to religious expression.

"The court has usurped the Constitution and converted it into a tool to drive religion from the public arena," said Christian Coalition Executive Director Randy Tate.

Both sides agree that the amendment would allow students to lead their classmates in sectarian prayer in the classroom the same way teachers lead students in the pledge of allegiance now. Morning prayers over intercoms, prayers from the podium at graduations and other school events, and expressions of personal religious views by teachers during class would also be permitted.

Students of minority religions or non-believers would have to remain silent or leave the room if they did not wish to participate.

Rep. Barney Frank, D-Mass., an opponent, said sponsors had no reason for backing the amendment except as a means to inculcate students they feel have been given no, or insufficient, religious direction at home.

Other expressions of faith by government officials and on government property would also be permitted under the amendment, including the posting of the Ten Commandments and crucifixes and the display of nativity scenes. Judges would be permitted to lead jurors and courtroom personnel in prayer.

"I think a lot of Americans are looking to go backward to get a feeling that we had when they were young, where you had a sense of community, where you could acknowledge your God if you choose to without forcing anybody else to do it your way," said Rep. Lindsey Graham, R-S.C., a supporter. "That's what this would do."

The amendment would also clear the way for public funding of religious schools and other religious activity.