Sen. John Kerry supports banning most abortions of fetuses post-"viability," the campaign confirmed Thursday.

Roughly 10,000 abortions occur each year in the third trimester, after fetuses are commonly thought to be viable, so this approach could curtail a greater number of late term abortions than the "partial birth abortion" ban often discussed by President Bush.

In 1997, when Congress was first considering whether to prohibit partial birth abortion, Democratic Sen. Tom Daschle of South Dakota offered a compromise amendment that banned abortion for any fetuses that could be considered viable. [Text here]. Kerry voted for the amendment, which was defeated by an alliance of Republicans and liberal Democrats. [Click here for roll call.]

Kerry has never mentioned his support of such a ban in any major speeches, debates or campaign documents and usually emphasizes a woman's "right to choose." However, in response to questions from Beliefnet concerning the 1997 vote, campaign spokesman Jim Chon, emailed Thursday, "John Kerry stands by his vote."

The Daschle amendment stated: "It shall be unlawful for a physician to abort a viable fetus unless the physician certifies that the continuation of the pregnancy would threaten the mother's life or risk grievous injury to her physical health."

At the time Daschle proposed his amendment, also called the "comprehensive abortion ban act of 1997," the American Civil Liberties Union attacked it as "unconstitutionally narrow" because it didn't allow enough health-of-the-mother exceptions. The National Abortion and Reproductive Rights Action League president Kate Michelman said Daschle's amendment "goes too far" in restricting abortion.

Republicans opposed the Daschle amendment too, arguing that it gave too much authority to doctors to determine "viability."

Though President Bush has spoken in general about the need to "protect life" -- and the Republican platform calls for a constitutional amendment banning most abortion -- it is the partial birth ban he mentions most often. There has been much debate about the actual number of late term partial birth abortions, with most estimates ranging from a few hundred to 1,500. The ban signed by President Bush did not affect other kinds of late term abortions.

Medical conventional wisdom holds that fetuses generally become viable - able to live outside the womb - by the beginning of the seventh month of pregnancy. The Alan Guttmacher Institute has estimated that .08% of abortions, or about 10,000, occur after the 24th week. The Daschle bill also would have prohibited any "partial birth" abortions of fetuses that were viable.

The Bush campaign has criticized Kerry's votes against the partial birth ban and the Bush-Cheney campaign's official website notes several other examples of Senator Kerry opposing restrictions on abortion. As a result of his pro-choice record, several Catholic bishops have said that voting for Kerry is a sin.

The Church's position -- and the Kerry campaign's statement -- may be significant because several battlegrounds states have large Catholic populations: Pennsylvania (30%), New Jersey (45.9%), Ohio (28%), Michigan (28%), Wisconsin (34.4), Minnesota (28.7%) and New Hampshire (38.2%), according to the Gallup Organization.

A TV ad being run by National Right to Life states: "John Kerry supports abortion for any reason, all nine months of pregnancy." A voters guide being distributed to churches around the country by the American Conservative Union says Kerry "never met an abortion he didn't like."

The Kerry campaign did not elaborate on the vote, or attempt to reconcile it with other votes the senator cast against partial birth abortion, a procedure which can occur in both the second or third trimester.

The 1997 fight created some unusual alliances. Two pro-life academics Stephen C. Meyer and David K. DeWolf wrote in the Wall Street Journal at the time that the Daschle amendment would have stopped more than 10,000 abortions each year.

The writers declared, "For Americans who want to limit abortion on demand, a historic opportunity stands open in Congress. Whether pro-life legislators seize this opportunity will depend on whether they prefer symbolic victory or substantive reform."

Several pro-choice groups opposed the approach. In a letter opposing the amendment, the ACLU stated at the time that the ban would "would prevent women with serious and legitimate health problems from obtaining the abortions they need."