During the 1928 presidential campaign, nutty right-wing Protestants claimed that Al Smith, the first Catholic nominated for president by a major party, was planning to extend New York’s Holland Tunnel all the way to the Vatican.

Today’s tunnel would run from the Vatican to a suburban Pentecostal megachurch.

We learned this week that U.S. Catholics support President Barack Obama’s Feb. 10 compromise on contraception in almost identical numbers to the population as a whole. Many of those sticking with the Catholic bishops in opposition are evangelical Protestants.

Historians are rubbing their eyes in wonder that the spiritual and political descendants of Protestants who founded the Know Nothing Party in the 1850s on anti-Papist ideas -- who hassled not just Al Smith but also John F. Kennedy for supposed ties to Rome -- are now embracing Catholics. Rick Santorum was recently greeted at Oral Roberts University by an enthusiastic crowd of 4,000.

Yes, politics makes strange bedfellows, and in this case, the Republicans, by throwing in their lot with the bishops, are using no protection. Like the controversy over the Susan G. Komen for the Cure foundation withdrawing support from Planned Parenthood over its provision of abortion services, this struggle leaves Republicans politically exposed.

Redefining the Debate

At first, the Komen case looked like just another example of anti-abortion activists flexing their muscles against hapless women’s health advocates. Then came a furious, highly effective counterassault fueled by liberal social media, a new counterweight to conservative talk radio in defining the terms of debate. The outcome of that flap, in which the Komen foundation reversed itself and apologized, shows that bashing Planned Parenthood may work in Republican primaries but will be poison in the general election.

The demand for “conscience” exemptions from Obamacare for Catholic hospitals, schools and charities (churches were already exempt) also looked good for the Republicans initially. Conservatives thought that they had a chance to revive the “culture wars” -- the wedge-issue appeals to faith and family that have worked so well in the past. For more than a week, Republicans made Obama look like the guy who ordered Joan of Arc burned at the stake.

Their problem is that they never know when to stop. Recall the case of Terri Schiavo, the Florida woman in a persistent vegetative state whose plight led conservative lawmakers to champion federal legislation in 2005 to keep her alive. The measure passed, but public opinion polls afterward showed the law was widely unpopular and a clear case of congressional overreach.

This time conservatives stuck with the argument that the president was abusing religious freedom even when that attack was no longer plausible. By decreeing that insurance companies, not Catholic institutions, will pay for contraceptives in employee health-care plans (as allowed under the Affordable Care Act), the president successfully shifted the subject back to birth control, where he’s on solid political footing.

Obama’s like a quarterback who calls a bad play and seems trapped in the pocket, then scrambles for big yardage.

Put Into Context

The bad play resulted from poor political planning inside the White House, which failed to line up supporters to defend its decision. But it’s a little more defensible when you know the context. For months, the pressure seemed to come from the left. The White House learned that 28 states (including Mitt Romney’s Massachusetts) already require that health plans under their jurisdiction cover contraceptives. These rules had survived court challenges on religious freedom grounds. In fact, women’s groups were threatening lawsuits if Obamacare didn’t also require such coverage, and some government lawyers argued that the new law provided no authority for any exemptions for institutions receiving federal money.

Obama’s team debated the issue and, contrary to published reports, the discussion didn’t break down cleanly along gender lines, with women on one side and Catholic men on the other. When the rule was made public on Jan. 20, White House press secretary Jay Carney faced not a single question about it. Then the regional and religious press embraced the story, and within a week even liberal Catholic columnists like E.J. Dionne and Mark Shields were up in arms.

But the firestorm may prove to be a political blessing. If the president had started on Jan. 20 with the compromise he eventually arrived at on Feb. 10, it would have been a one-day story for health-care policy wonks. Birth control would never have surfaced as a political issue.

Instead contraception is now the elephant in the bedroom -- the issue that no one in the Republican establishment wants to talk about because they know it’s a disaster for them.

The Republicans may end up with a nominee, Rick Santorum, who has warned of “the dangers of contraception in this country.” He said: “It’s not OK because it’s a license to do things in the sexual realm that is counter to how things are supposed to be.”

This from a candidate who recently said of the president: “He thinks he knows better how to run your lives.”

Imagine what Obama would do with that in a debate.

Instead of running away from Santorum, many Republicans are running toward him -- once again, failing to get the memo on when to stop. Senator Scott Brown co-sponsored a bill this week with Senator Roy Blunt that would let any employer with a “moral conviction” (a term left undefined in the legislation) deny access to any health service, including contraception, they personally oppose. This weapon is aimed at Obamacare, but it will probably boomerang on Brown, who is locked in a tight re-election campaign in Massachusetts against Elizabeth Warren.

With all the major candidates this year enjoying seemingly happy marriages, it didn’t seem as if sex would figure much in this campaign. Wrong. The independent women who will help determine the election want the government -- and their bosses - - out of their private lives.

The culture wars are over, and the Republicans lost.

(Jonathan Alter is a Bloomberg View columnist and the author of “The Promise: President Obama, Year One.” The opinions expressed are his own.)

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To contact the writer of this article: Jonathan Alter at alterjonathan@gmail.com.

To contact the editor responsible for this article: James Gibney at jgibney5@bloomberg.net.