Updated

Senate Democrats have blocked an amendment that would have let insurers opt out of providing contraceptive coverage if employers had religious or moral objections.

The Respect for Rights of Conscience Act, shorthanded as "the conscience amendment" and authored by Sen. Roy Blunt, R-Mo., was "tabled," or set aside, on a 51-48 vote.

Democrats needed 50 votes to prevail.

Blunt's amendment to a transportation bill would exempt employers from a new government mandate, soon to be put in place under the Patient's Protection and Affordable Care Act.

Blunt, on the Senate floor shortly before the vote, staunchly defended his proposal and said it would not fade away no matter the outcome Thursday. Firing back at critics, the senator said the measure would do nothing to change existing policy. It would only apply to new health care overhaul provisions that have not yet taken effect.

Blunt, in a separate statement, said the proposal "simply preserves and protects the fundamental religious freedom that Americans have enjoyed for more than 220 years." He decried "blatant attempts to frighten and mislead Americans" about the measure.

Democrats, though, said the proposal went too far and could threaten access to care.

"It appeals to the social agenda of a small, very vocal part of the Republican Party," Senate Democratic Leader Harry Reid said.

Click here to see the vote breakdown in the Senate.

Obama's policy decision was rewritten last month under pressure from Catholic bishops and others. It now requires health insurers to cover birth control for employees even of religiously affiliated institutions whose beliefs conflict with contraception. As part of his original health care overhaul, the policy required employers providing health care insurance to their workers to cover contraceptives.

The Catholic bishops and many conservatives say that still infringes on religious freedom.

The issue has started a bitter and fierce dialogue over how much power the government should be able to wield over religious institutions in regards to the benefits they provide their employees, and is shaping up to be a hot topic in the 2012 election.

Politicians from both parties, eager to rouse their respective political bases in an election year, have been quick to slam the other side over their stance on the issue.

Republicans say Obama's requirement violates the freedom of religion because it forces some organizations to cover contraception even though their faith forbids it.

In a statement issued Wednesday evening, Richard M. Doerflinger, the Secretariat of Pro-Life Activities for the U.S. Conference of Catholic Bishops, said Blunt's measure had been created to prevent religious institutions from having to choose between honoring their beliefs and honoring their commitment to cover health care for their employees.

He said Senate Democrats' claims that the bill would cause 20.4 million women now receiving coverage for preventive services to lose that coverage are "preposterous."

"The Blunt amendment does not modify state or federal laws that are now in effect," he said. "It only amends the new mandated benefits provisions in Title I of the Health Care Reform Act of 2010 (PPACA), supplying the respect for religious beliefs and moral convictions that is already part of other federal health programs, but is woefully missing from PPACA."

However, Democrats have cast the bill as an attempt by Republican leaders, under pressure from religious authorities, to limit women's access to birth control.

They claim the bill is "a wolf in sheep's clothing," and may allow employers to exclude coverage for any conditions they find religiously or morally objectionable.

They also say this could become a slippery slope, resulting in the exclusion of coverage for HIV & AIDS, mental health, hemophilia, STDs and more.

"Let's beat the Blunt amendment. It's a disaster. It's dangerous," said Environment and Public Works Chairman Barbara Boxer, D-Calif., arguing that it endangers 2.8 million jobs that are said to be created from the transportation package.

Sen. Barbara Mikulski, D-Md., who wrote the section of the health care law that includes the new preventative coverage, charged that Republicans were really just trying to take it down, calling the amendment a "masquerade."

Senate Republican Leader Mitch McConnell, however, called the new Health and Human Services mandate "a government takeover," saying it is "precisely the kind of thing the Founding Fathers feared" -- an infringement on the First Amendment right of freedom of religion.

The issue lit a flame under the simmering culture war and has now spilled into the presidential race of 2012.

Former Massachusetts Gov. Mitt Romney initially said he opposed the Blunt amendment Wednesday night, igniting a brief firestorm. Democrats quickly rushed the news to reporters. Romney's GOP primary opponent, former Sen. Rick Santorum, R-Pa., immediately blasted the governor.

Within moments of the news hitting, the Romney campaign had walked it back, saying the governor supports the Blunt measure and was merely confused by a reporter question.
The political brushfire is just a glimpse of the pressure on these Republican candidates to hew close to conservative principles.

The Obama administration blasted Blunt's amendment in a press release Wednesday, saying the president's supporters need to "stand for a woman's right to make her own health decisions."

"This is an issue for everyone," the release said. "We're not about to sit back and let the other side tear down access to better care."

Fox News' Trish Turner contributed to this report.