(CNN)The Senate is on track to hold a key vote Wednesday on a bill aimed at preserving access to abortion nationwide. It comes as the US Supreme Court may be poised to overturn the landmark 1973 Roe v. Wade ruling as soon as next month, as indicated by a leaked draft opinion.

       The vote is expected to fail amid widespread Republican opposition to the measure. As a result, the Senate will fall far short of the support needed to overcome the 60-vote threshold needed to pass most legislation in the chamber. Sen Joe Manchin, a moderate Democrat from West Virginia, will join with Republicans to oppose the bill, highlighting a divide over the issue of abortion among Democrats.

       Manchin told CNN ahead of the vote he will be a "no" on the Democratic bill, arguing it's too broad. He indicated he would support a codification of Roe v. Wade, but said this bill goes too far.

       The bill's failure to advance is set to underscore how Democrats are severely limited in what they can achieve with their narrow Senate majority even as the party faces enormous pressure to take action on abortion rights amid fears that Roe v. Wade will soon be struck down. But holding the vote will give Democrats a chance to spotlight the issue and criticize Republican resistance to passage of the legislation.

       Senate Majority Leader Chuck Schumer called the vote one of the "most important" senators will take, "not only this session, but in this century."

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       "This is not an abstract exercise, it's as real and as urgent as it gets," Schumer said at a news conference on Friday.

       The Senate will be voting to advance a version of the Women's Health Protection Act sponsored by Democratic Sen. Richard Blumenthal of Connecticut. The bill would codify the right to access abortion into federal law and guarantee the right of health care providers to perform abortion services. A House-passed version of the bill failed to advance in the Senate earlier this year amid GOP opposition.

       Senate Minority Leader Mitch McConnell blasted Democrats for forcing a vote this week codifying the Roe v. Wade decision, arguing that "it would attack Americans' conscience rights and religious freedoms."

       "It would overturn modest and overwhelmingly popular safeguards like waiting periods, informed consent laws and possibly even parental notification," McConnell said of Democrats' bill in remarks on the Senate floor on Monday.

       The vote also underscores how there isn't unity over the contentious issue even among Democrats. Manchin, who represents the red state of West Virginia and has previously described himself as "pro-life and proud of it," also voted with Republicans in opposition to the bill when it came before the Senate in February.

       Sens. Susan Collins and Lisa Murkowski, rare Republican abortion-rights supporters, have introduced their own legislation to codify the rights established by Roe into federal law.

       But both voted against the Women's Health Protection Act in February. Collins criticized the Democratic bill in a statement on Wednesday ahead of the vote. The Maine Republican said the bill "explicitly invalidates the Religious Freedom Restoration Act in connection with abortion and supersedes other longstanding, bipartisan conscience laws, including provisions in the Affordable Care Act, that protect health care providers who choose not to offer abortion services for moral or religious reasons."

       Asked at a news conference on Friday why he won't instead bring the Collins and Murkowski bill to the floor, which could receive bipartisan support, Schumer said, "We are not looking to compromise something as vital as this."

       Earlier this week, more than a dozen abortion rights groups wrote a letter strongly opposing Murkowski and Collins' bill, arguing it "would not protect the right to abortion if Roe v. Wade is overruled."

       Democrats have sounded the alarm and reacted with outrage in response to a recently leaked Supreme Court draft opinion revealing plans to strike down Roe v. Wade after roughly five decades.

       Republicans, despite many opposing abortion rights, have focused their response instead on the bombshell leak of the Supreme Court opinion, arguing that the leak itself represents a significant threat to judicial independence and freedom from outside interference.

       While the Senate vote on Wednesday had been expected to fail, many Democrats still argued that the political landscape has shifted now that it has become evident Roe v. Wade may soon be struck down and that it is imperative to put lawmakers on the record over the issue.

       "I do think that the vote is necessary," Rep. Cori Bush, a Missouri Democrat, said. "There has been time since (the bill) failed in the Senate the last time for people to have more conversations, more outreach. And then when this news of the leak, the draft opinion, when that became public, for a lot of work, a lot of conversations, a lot of advocacy groups reaching out, a lot more information stirring in people's communities to open up a conversation where people could have a mind change."

       This story has been updated with additional developments Wednesday.

       CNN's Manu Raju and Ted Barrett contributed.