Smith, who is trying to unseat Democratic Sen. Bob Casey, made the remarks after appearing at the monthly Pennsylvania Press Club luncheon, where he argued for shrinking the federal bureaucracy and rolling back the Affordable Care Act.
After the speech, Smith was asked about Republican U.S. Rep. Todd Akin's recent comments on abortion and rape. The GOP's Missouri candidate for the Senate, Akin sparked a firestorm when he said victims of "legitimate rape" rarely become pregnant because their bodies then tried to prevent conception. His remarks have prompted ridicule from medical experts and calls by fellow Republicans, including Mitt Romney, that he withdraw from the race.
Smith said Akin should never have made those comments, then reiterated his own no-exceptions position on abortion.
Asked by a reporter how he would counsel a daughter or granddaughter who had been impregnated by rape, Smith said: "I lived something similar to that with my own family. She chose life, and I commend her for that. . . . Don't get me wrong; it wasn't rape."
Pressed as to what he was talking about, Smith responded: "Having a baby out of wedlock." After that, he seemed to struggle to articulate what he meant.
"That's similar to rape?" a reporter asked.
"No, no, no," said Smith, who was referring to a daughter's decision to have a child outside marriage. Then he added, "But, well, put yourself in a father's position. Yes, I mean, it is similar."
Pressed later about whether he was saying that having a baby while unmarried was analogous to having a baby as a result of rape, Smith said, "I never said that. I didn't even come close to that."
"Do I condone rape?" he said. "Absolutely not." He added: "I am pro-life, period. . . . A life is a life, and it needs to be protected."
A spokesman for Casey's campaign declined to comment Monday. Like Smith, Casey opposes abortion, but he says he would make exceptions in cases of rape or incest, or to protect a mother's life.
The Democratic National Committee was quick to send an e-mail in an effort to bring attention to Smith's remarks.
An Inquirer Pennsylvania poll released this weekend showed that if the election were held today, voters would handily return Casey to Washington.
The Democratic senator held a 19-point lead over Smith and appeared to be benefiting from high name recognition. Few voters polled reported familiarity with Smith.
Smith acknowledged Monday he was starting from a political disadvantage - "I don't have a famous political name, but I do have a simple name."
His plan, he said, is to work at "reintroducing" himself to voters and point out differences between his and Casey's positions.
"It's a long time until Election Day," Smith said. "A lot can happen between now and then."
Contact Angela Couloumbis at 717-787-5934 or acouloumbis@phillynews.com, or follow on Twitter @AngelasInk.