(CNN) – On the 40th anniversary of the benchmark Supreme Court decision of Roe v. Wade, new poll numbers indicate growing opposition to overturning the ruling, a move advocated by many in the anti-abortion movement.
The 1973 ruling affirmed the legality of a woman's right to have an abortion under the Fourteenth Amendment. In a 7-2 decision, the ruling allowed for legal abortions during the entire pregnancy, but set up conditions to allow states to regulate abortion during the second and third trimesters.
According to a new NBC News/Wall Street Journal poll, 39% of Americans say they approve of the decision, while 18% say they disapprove and 41% say they don't know enough about the ruling to have an opinion.
However, 70% say they would not like to see it overturned, with 57% of them saying they feel strongly about their opinion. The 70% mark is the highest number in support of keeping the law since the poll was first conducted in July 1989, when 58% felt the same way.
The change can be attributed to African Americans, Latinos and women without college degrees, three groups that increasingly oppose the overturning of the Supreme Court decision, according to NBC/WSJ pollsters.
On the other hand, 24% say they want to see the decision reversed, with 21% of them saying they have strong feelings about the issue. That number is down from 2005, when 30% said they wanted to do away with the law, and 31% in 1989.
READ MORE: Before and after Roe v. Wade
Breaking it down by more detailed arguments, a plurality of Americans say there should be some exceptions to abortions. Thirty-five percent say the practice should be illegal except in the cases of rape, incest and to save the life of the mother. Thirty-one percent, meanwhile, said it should always be legal and 23% said it should be legal most of the time.
A small minority–nine percent–oppose abortion fully, meaning they think it should be illegal without any exceptions. Two percent say they are unsure.
Political dialogue in the country also saw a surprising but highly-charged debate over abortion and contraception within the last year. Last winter kicked off with sharp disagreement over an Obama administration rule that initially called for religiously-affiliated institutions to include coverage for contraception in their health care plans. And two Senate races brought the topic to the national spotlight when Republican candidates made controversial statements about rape and abortion.
According to a recent CNN/ORC International poll, a majority of Americans–53%–say they approve of how President Barack Obama has handled the issue of abortion, while 35% say they disapprove. Taking a closer look at gender, men and women are basically close on the issue, the poll indicates.
In TV ads, the president's re-election campaign attacked Republican presidential nominee Mitt Romney for saying he opposed Roe v. Wade. The president was also critical of Richard Mourdock and Todd Akin, the two GOP Senate candidates who sparked uproar over their comments about rape and pregnancy.
While Akin said a woman's body is capable of preventing pregnancy during the trauma of "legitimate rape," Mourdock said he opposed abortion even after a rape, because the pregnancy was "something that God intended to happen." Both apologized for their comments.
The president, however, said in an October interview with NBC's Jay Leno that he doesn't know "how these guys come up with these ideas."
"This is exactly why you don't want a bunch of politicians, mostly male, making decisions about women's health care decisions," Obama continued. "Women are capable of making these decisions in consultation with their partners, with their doctors, and for politicians to want to intrude in this stuff often times without any information is a huge problem."
The NBC/WSJ survey was conducted by telephone with 1,000 adults nationwide from January 12 through January 15. The poll's sampling error is plus or minus 3.1 percentage points.
The CNN/ORC International Poll was conducted January 14 through January 15 with 814 adults via telephone. The poll's sampling error was plus or minus 5 percentage points.
– CNN Political Editor Paul Steinhauser contributed to this report.