US Senate candidate Richard Mourdock drew fire late on Tuesday after saying that pregnancies caused by rape were "something God intended to happen" while defending his opposition to abortion.
Republican White House hopeful Mitt Romney was quick to distance himself from the gaffe as Democrats pounced, sensing an opening to brand him as an extremist among vital women voters less than two weeks ahead of election day.
Speaking at a Senate debate, Mourdock said he believed life begins at conception and opposed abortion in all cases except when the mother's life was in danger.
"I struggled with it myself for a long time, but I came to realise life is that gift from God, and I think even when life begins in that horrible situation of rape, that it is something that God intended to happen," he said.
Indiana Democratic Party Chair Dan Parker quickly responded, issuing a statement saying that "as a pro-life Catholic, I'm stunned and ashamed that Richard Mourdock believes God intended rape.
"Victims of rape are victims of an extremely violent act, and mine is not a violent God. Do we need any more proof that Richard Mourdock is an extremist who's out of touch with Hoosiers?" he asked, referring to Indiana natives.
Romney's campaign moved to distance him from the remarks, with spokeswoman Andrea Saul saying "Governor Romney disagrees with Richard Mourdock's comments, and they do not reflect his views."
Romney has said he opposes abortion except in cases of rape or incest, or to save the mother's life.
The exchange threatened to put the divisive issue of abortion front and center in the closely-fought presidential race.
President Barack Obama has long accused Romney and other Republicans of having extreme views on abortion and other women's rights, and the Democratic National Committee quickly moved to link Romney to Mourdock.
The committee sent a link to a television ad in which Romney endorsed Mourdock, saying he would be "the 51st vote to repeal and replace government-run healthcare," referring to Obama's landmark reforms.
The ad did not mention abortion or other social issues.
With the two candidates neck-and-neck, women voters in crucial swing states could decide the November 6 election.
In the final presidential debate Monday night, Obama accused Romney of wanting to take America back to the "social policies of the 1950s."
Romney has vowed to be a "pro-life president," and his current presidential platform supports overturning the 1973 Supreme Court decision that legalized abortion, letting states decide on the legality of the practice.
Another Republican Senate candidate, Todd Akin of Missouri, sparked controversy in August when he said that a woman's body could prevent conception in cases of "legitimate rape."
Those remarks brought an avalanche of condemnation from both political parties and from Romney himself. Akin apologized for the remarks, but refused Republican demands to quit the race.
Akin's refusal to step down raised doubts about whether Republicans would be able to wrest back control of the 100-member Senate from Democrats in congressional elections, also due to be held November 6.