WASHINGTON – High-priority Republican legislation aimed at curtailing abortion rights across the United States is on its way to passage in the House, having secured enough co-sponsors for approval on the floor.

Sponsored by Rep. Chris Smith (R-NJ), H.R. 3, "The No Taxpayer Funding For Abortion Act," would eliminate employer deductions for health insurance if the plan includes abortion, effectively raising costs for employees' health insurance.

By Wednesday, hours before a Ways and Means subcommittee markup of the bill, it had gained 221 official co-sponsors, crossing the 218 threshold necessary for passage.

The legislation may be a lost cause in the Democratic-led Senate -- nor would President Barack Obama be inclined to sign it -- but House passage would nevertheless be a shot across the bow for abortion-rights advocates, who would suffer arguably their most significant defeat since the Hyde Amendment of 1976.

It also provides politically useful fodder for the fiercely anti-abortion conservative base ahead of the 2012 elections, in which the GOP sees the Senate and White House as up for grabs.

"H.R. 3 takes the unprecedented step of manipulating the federal tax code to push an extreme anti-choice agenda, which is why the House's tax-writing committee is granting it a hearing," said Nancy Keenan, president of the abortion-rights group NARAL.

"This bill imposes tax penalties on small businesses and many individuals who purchase private insurance plans that cover abortion care. This begs the question -- what incentive does a private-insurance company have to provide coverage for this safe and legal procedure if their customers are going to suffer a tax hike?  Since 87 percent of private-insurance plans currently cover abortion care, the effects of H.R.3 would be devastating."

The Wednesday hearing by the Ways and Means Subcommittee on Select Revenue Measures, scheduled for 2:00 pm Eastern Time, isn't expected to contain any major changes as the legislation has largely taken shape.

"The Ways and Means Committee has a responsibility to lend our tax policy expertise to the development of H.R. 3 to ensure that the relevant provisions serve their intended purpose," said Rep. Pat Tiberi, (R-OH), chairman of the subcommittee.

The bill initially sparked immense controversy over original language that would have denied longstanding exemptions on abortion coverage for victims of rape, incest and when the woman's life is in danger. Those provisions were stripped out during a Judiciary Committee markup two weeks ago.

But even the new version contains a departure from the Hyde exemptions, declaring that federally-assisted abortion coverage may be denied to a woman even if carrying a pregnancy to term would adversely affect her health.