It began as one of the nation’s broadest proposed bans on religious exemptions to childhood vaccines.

But after weeks of sustained and boisterous protests by vaccine sceptics, as well as a last-minute effort to amend the proposed bill to win the support of key lawmakers, the effort collapsed Monday in the New Jersey state Senate.

The Senate president, Stephen M. Sweeney, maintained that science, not protesters, would eventually emerge victorious.

“It’s going to get done,” Mr Sweeney, a Democrat, said, repeating a vow he had made since last month when a far more sweeping version of the bill passed in the Assembly but failed to win enough support in the Senate. Democrats control both chambers.

“They can bang on their drums and their sirens and their truck horns,” Mr Sweeney said over the din of protesters after it became clear that the measure was a single vote shy of passage. “This is a real public health emergency.”

The famous faces of the anti-vaccine movement Show all 7 1 /7 The famous faces of the anti-vaccine movement The famous faces of the anti-vaccine movement Charlie Sheen Sheen fought a legal battle against ex-wife Denise Richards to try and block her from vaccinating their children. Richards of course won and Sheen was reportedly so bitter that he paid the paediatrician bill entirely in nickels Getty The famous faces of the anti-vaccine movement Gwyneth Paltrow Paltrow's "health and wellness" company Goop hosted a notorious anti-vaccine speaker at their 2018 Goop Summit Getty The famous faces of the anti-vaccine movement Rob Schneider Schneider demanded the freedom to decline vaccination Getty The famous faces of the anti-vaccine movement Jenny McCarthy McCarthy has claimed that "people are dying from vaccinations", believes that her son caught autism from a vaccine and has pushed her opinions on the topic publicly for many years AFP/Getty The famous faces of the anti-vaccine movement Bill Maher Maher has long spoken against vaccines sating on Larry King live that "a flu shot is the worst thing you can do." His stance appears to stem from a distrust of government AFP/Getty The famous faces of the anti-vaccine movement Alicia Silverstone In Silverstone's book The Kind Mama, she wrote that "there is increasing anecdotal evidence from doctors who have gotten distressed phone calls from parents claiming their child was ‘never the same’ after receiving a vaccine." Getty The famous faces of the anti-vaccine movement Andrew Wakefield Godfather of the anti-vax movement, disgraced doctor Andrew Wakefield famously published a report in the medical journal Lancet claiming a link between the MMR vaccine and autism in 1998. The Lancet retracted the report in 2010 and Wakefield was struck off the medical register PA

The bill would have ended a policy that allows parents in New Jersey to cite religious beliefs as the reason their children have not been immunised, without affecting the child’s ability to be enrolled in school.

Doctors and public health experts had said the original bill was urgently needed to prevent the kind of measles outbreak that occurred in the region last year. They emphasised that there is an overwhelming scientific consensus that vaccines are safe and effective.

Sen Loretta Weinberg, a Democrat and a sponsor of the legislation, said that the Senate would immediately reintroduce a new version of the bill and begin the process anew. This time, she said, the Legislature might hold public hearings with doctors and scientists to debunk opponents’ concerns.

“The science is settled on this,” Ms Weinberg said.

In its original form, the bill would have included all students enrolled in any school or college, public or private, making it one of the most sweeping among the several states that have voted to end religious exemptions to immunisation.

Only medical exemptions from vaccines would have been permitted at most schools and daycare centres.

But the legislation was altered last week to apply only to public schools, a change that appeared to raise new concerns, even among lawmakers who had supported the original legislation.

The private schools and daycare centres that would have been exempt under the amended version of the bill would have been required to collect and share data on the number of enrolled students who had not been fully immunised.

The proposed compromise did nothing to quell the anger of the hundreds of protesters, who packed the courtyards outside the state House on Monday, as they have done regularly over the past two months. Children banged on makeshift drums as parents shouted into megaphones. One man sounded what appeared to be a shofar, the ram’s horn instrument used for Jewish religious purposes.

“Parents call the shots,” one sign read. “My God. My body. My right,” read stickers worn by many of the protesters.

After the Senate adjourned just after 6 pm without voting on the vaccine measure, on the final day of a two-year legislative session, the crowd outside roared.

“Thank you, God,” one group chanted.

The intensity of the prolonged protest was unlike anything in Trenton in more than a decade, many longtime lawmakers and lobbyists said.

States that have limited or revoked religion-based vaccination exemptions include California, Mississippi, Maine and New York, which was at the epicentre of a measles outbreak last year.

In New Jersey, Assemblyman Herb Conaway, a Democrat and a practising doctor who was one of the legislation’s sponsors, defended the compromise bill in an interview before it unravelled.

“We’ve had to make some concessions,” Mr Conaway said.

“Vaccines are safe,” he added, “and we in public health need to say that repeatedly.”

Still, the amended version of the bill remained deeply unpopular with protesters who cited religious, constitutional and medical reasons for their opposition.