Senate Republicans on Thursday blocked legislation that would codify the right to access fertility treatments such as in vitro fertilization, in the latest election-year bid by Democrats to spotlight G.O.P. opposition to protecting reproductive freedoms.

On a vote of 48-47, all but two Republicans opposed advancing the bill, which would give Americans the statutory right to receive fertility treatments and decide how their reproductive material is used, stored and disposed. That left the measure well short of the 60 votes it needed to move forward, an outcome Democrats anticipated and even welcomed as part of their strategy to remind voters where Republicans stand on issues of abortion and reproductive health.

“We’re going to keep working with Republicans,” Senator Chuck Schumer, Democrat of New York and the majority leader, told reporters at a news conference before the vote. “But they seem to be totally in the throes of the MAGA hard-right minority on this issue.”

The action came a week after a test vote on a bill that would enshrine nationwide access to contraception in federal law, which Republicans also blocked.

It also came the day after Southern Baptists, the country’s largest Protestant denomination and a bellwether for the larger American evangelical movement, voted to oppose the use of I.V.F. That decision could put many conservative lawmakers in an even tougher political position on the issue.

Republicans have struggled to find a winning message on I.V.F. that appeases their far-right evangelical base without alienating more mainstream conservatives. Many of them support legislation that declares that life begins at conception, which could severely restrict aspects of I.V.F. The treatment typically involves creating several embryos, freezing them and implanting only one or two. At the same time, many conservative lawmakers quickly voiced their support for fertility treatments after a decision by Alabama’s Supreme Court in February that frozen embryos should be considered children.