John McCain’s choice of Sarah Palin as his running mate was a masterstroke, if for only one utterly decisive reason: It suddenly, overnight, energized the pro-life vote, the 2000 and 2004 “values voters” that twice made the difference for George W. Bush.

McCain had struggled to ignite that base. This influential, highly committed group of churchgoing voters, churchgoing Catholics and evangelicals, was appalled by Barack Obama’s awful statements and actions toward the unborn — and the newly born. That is a powerful reason for them to vote against Obama.

But a negative vote rarely drives people in droves to the polls. The Christian faith is one of optimism, as Jesus Christ literally preached faith, hope and love. And pro-life Christians typically need to vote in favor of someone more than against someone else.

Sarah Palin, with her impeccable pro-life credentials, both personally and politically, along with the views of both John and Cindy McCain, gives them what they need to eagerly show up for John McCain on Nov. 4.

I understood this the moment I heard the Palin choice, and it took my e-mail box less than an hour to confirm it over and over. I’m convinced that if John McCain is elected president in November, it will be in large part due to the Palin pick.

And within that is a remarkably powerful sub-symbol relating to the abortion issue in this presidential showdown: This election may come down to a tale of two babies with Down syndrome.

The first of the two babies is obvious: Sarah Palin, a mother of four in her 40s, a governor, a very busy working woman who already “had it all,” was told only 10 months ago that the child she was carrying in her womb had Down syndrome. True to her principles and integrity, she chose life when other mothers choose abortion. That baby, born in April, is now a member of her family. It was a choice that has thrilled pro-lifers and has excited them more than any other aspect of the Palin pick.

It is a beautiful reminder of the difference between the McCain-Palin and Obama-Biden tickets.

Obama and Biden are both pro-abortion, with the latter a “pro-choice Catholic” — technically impossible, according to the Catechism of the Catholic Church and 2,000 years of official Church teaching.

Still, Biden is an abortion moderate compared to the abortion extremist at the head of the ticket. And as is now well-known, there’s no better illustration of that extremism than Barack Obama voting against Illinois legislation to provide medical care to babies who survived abortions.

That was a choice Obama made out of a highly implausible, tragic and factually incorrect fear that the legislation would undermine the sanctity of Roe v. Wade. In his mind, Roe became a greater loyalty than those dying newborns.

Obama’s intransigence was best shown in the eyewitness experience of Jill Stanek, the nurse at Christ Medical Center in Oak Lawn, Ill., who provided testimony to Obama’s committee in the Illinois Senate. To Stanek’s amazement, Obama was unfazed by her devastatingly sad testimony of cradling a newborn baby who had just survived an abortion. That baby was refused medical care. He was sent to the soiled utility room to endure a heart-wrenching, excruciating death over the course of 45 minutes.

“He was too weak to move very much,” remembered Stanek, in testimony for which the hospital fired her, “expending any energy he had trying to breathe. Toward the end, he was so quiet that I couldn’t tell if he was still alive unless I held him up to the light to see if his heart was still beating through his chest wall.”

Why was this poor, innocent, helpless little boy sentenced to this unjust, wicked execution? Because of this crime: He had Down syndrome.

That Down syndrome child was unable to affect Obama’s oft-expressed “least-of-our-brothers” compassion and protection.

But a Down syndrome child fully received Sarah Palin’s motherly compassion and protection. And pro-lifers everywhere feel the difference in this selective “social justice.”

Though I have not heard anyone explicitly draw this precise contrast between these two babies, I sense it is already coalescing in the consciences of many pro-lifers.

The angry pro-abortion, secular left will jump all over pro-lifers like me and these “values voters” who carry this contrast foremost in heart, mind and spirit as we go inside the voting booth this fall. They will call us names, denigrate our intelligence, and delude themselves into disregarding us and our “simple” ideas. That’s fine. Jesus warned us that we would be treated this way. Personally, I’m not bothered by the contempt of a group that has taken something as unholy as unlimited abortion on demand and made it an ironclad, dogmatic, defining element of their political party for more than two decades.

The pro-choice, secular left has wedded itself to the culture of death through its championing of “abortion rights.” And now, yet again, in 2008 — as in 2004 and 2000 — it will feel the difference at the voting booth.

By the way, the name of that Down syndrome baby held by Sarah Palin is Trig. The name of the Down syndrome baby held by Jill Stanek is not known. He never made it that far. On Nov. 4, 2008, however, that baby will not be forgotten.

Author Paul Kengor,

professor of political science at Grove City College, wrote

The Crusader: Ronald Reagan and the Fall of Communism

(Harper Perennial, 2007).