Republican Sen. Randi Becker of Eatonville, chairwoman of the Senate Health Care Committee, announced that the bill would not move forward hours after her panel heard testimony on it.
"Even advocates of the bill admit that there is no need for the bill today as every health insurer in the state of Washington provides for abortion coverage," said Becker in a written statement. "As such, the decision of the committee is that the bill will not move forward from here this year."
Her announcement makes clear that special measures would be required for the bill to get to the Senate floor for a vote.
The letter in support of the measure - dated March 5 but made public Monday - was signed by 25 of 49 state Senators and presented at the packed committee hearing where the bill was debated. After the hearing, frustrated supporters, who had long demanded a hearing on the measure, dismissed it as little more than a charade.
"It was just for show," said Sen. Karen Keiser of Kent, one of four Democrats on the nine-member panel. "It was simply a way to provoke a circus in the sense of having a lot of people show up and wave their ideological persuasions in front of us."
The hearing attracted more than 250 people from both sides of the abortion issue, with many of those wearing rival buttons and ribbons and dressed in dueling color schemes left to watch the proceedings on a screen in a nearby room.
The bill, which supporters call the Reproductive Parity Act, was passed by the House by a 53-43 vote in February, with mostly Democrats in favor and Republicans opposed.
Gov. Jay Inslee, a Democrat and a bill supporter, has repeatedly urged the Senate to vote on it.
The bill would make Washington the first state to require insurers that cover maternity care - which they all most do - to also pay for abortions. Similar legislation has been introduced each session in the New York State Assembly for over a decade but has never received a public hearing.
In testimony before Becker's committee, those supporting the measure said it would ensure continued abortion coverage in the state once federal health care reforms taking effect next year trigger bureaucratic hurdles for insurers paying for the procedure.
The bill would ensure that a woman's decision about whether to get an abortion "is left with her, her family, her health-care provider and her God," said Elaine Rose, CEO of Planned Parenthood Votes Northwest, addressing the committee. "Not with government, not with her insurance plan, and with all due respect, not with any of you."
Opponents countered that abortion insurance coverage is already widespread in the state and that the bill is unnecessary. They also said the measure threatens the religious freedoms of businesses and individuals who oppose abortion rights and do not want to subsidize the cost of the procedure for others.
"You all have the second amendment right to bear arms, to own a gun," said Peggy O'Ban, spokeswoman for Human Life of Washington. "But does that mean I have to buy it for you?"
Shortly after the hearing, Sen. Mike Padden, R-Spokane Valley, told bill opponents gathered in the hearing room that momentum was on their side, but encouraged them to keep applying pressure on lawmakers to help ensure it doesn't receive a vote in the full Senate.
Becker declined to answer a reporter's questions immediately following the hearing and did not respond to subsequent phone calls seeking comment.