Washington, DC (LifeNews.com) -- Republican presidential candidate Mike Huckabee is under fire from Jewish groups after a speech he gave at a pro-life event the weekend before last. In the address to the Family Research Council, the former Arkansas governor referred to the deaths of 45-50 million unborn children from abortion as a holocaust.

In the speech, he linked the issues of abortion and illegal immigration -- saying the destruction of tens of millions of unborn children has left the U.S. with a worker shortage.

“Sometimes we talk about why we’re importing so many people in our work force,” Huckabee said in the speech.

“It might be for the last 35 years, we have aborted more than a million people who would have been in our work force had we not had the holocaust of liberalized abortion under a flawed Supreme Court ruling in 1973," he explained.

Following the speech, the Anti-Defamation League called on presidential candidate Mike Huckabee to refrain from invoking Holocaust imagery in future comments on the campaign trail.

In a letter to Governor Huckabee, ADL National Director Abraham H. Foxman said: "The Holocaust was a unique tragedy in human history."

"We find the use of analogies to the Holocaust in other contexts deeply painful, disturbing and offensive," Foxman said. "Such analogies can only trivialize and diminish the horror, and cause further pain to Holocaust survivors and to those alive today who lost friends and loved ones."

But pro-life advocates have now come to Huckabee's defense saying that his use of the term was not meant as an offense to Jewish people but to underscore the equal tragedy in the destruction of human life.

Kristi Hamrick, a spokeswoman for the Campaign for Working Families, told The Jewish Daily Forward, “I’m surprised that it’s considered controversial when that is a common reference."

“Among pro-lifers, both events are seen as tragic, but the death toll now from abortion is between 40 and 50 million in the United States since 1973," Hamrick explained. "Now that’s a huge number of people who are dead and gone.”

Asked if he approved of Huckabee’s use of the word “holocaust,” Marvin Olasky, a conservative columnist and onetime Bush adviser, told the newspaper, he believed the word was “objectively” accurate.

Olasky said Huckabee used the term “honestly and respectfully" but he is generally “subjectively uncomfortable” with the word’s adoption by those who oppose legalized abortion.

Huckabee has been picking up more support lately in the polls, in part because some of the pro-life advocates who had been in Sam Brownback's camp shifted to him.