In an essay published by the National Review said Trump is "manifestly unfit to be president of the United States."

The essay, "An Appeal to Our Fellow Catholics," was co-written by Princeton professor Robert P. George and St. John Paul II biographer George Weigel.

The call has been supported by about three dozen lay Catholics, many of whom are active in conservative academic and nonprofit circles.

The group called on Catholics "to reject [Trump's] candidacy for the Republican presidential nomination by supporting a genuinely reformist candidate."

The article criticized Trump's "appeals to racial and ethnic fears and prejudice" that are "offensive to any genuinely Catholic sensibility" and his promise to kill the families of terrorism suspects.

"There is nothing in his campaign or his previous record that gives us ground for confidence that he genuinely shares our commitments to the right to life, to religious freedom and the rights of conscience, to rebuilding the marriage culture, or to subsidiarity and the principle of limited constitutional government," read the article.

After a visit to the US-Mexico border last month, Pope Francis said politicians who advocate building border walls aren't Christian. Trump then lashed out at the pope, saying it was offensive for the pontiff to question anyone's religious beliefs.

Several US bishops have condemned Trump's rhetoric on immigration, suggesting the candidate is engaging in modern-day nativism, resurrecting the kind of bigotry once directed at Catholics.

Sources

• National Review
• Christian Today
• The Washington Times
• Breitbart.Com
• Crux
• Image: AP/The Washington Times

As Republicans were promoting themselves as a multiracial party from the platform in Tampa two weeks ago, an ugly incident on the convention floor suggested not everyone had got the memo. From the podium a range of speakers of Haitian, Mexican, Cuban and Indian descent spoke of how their parents had overcome huge barriers so they could succeed in the US. In the audience, a successful black woman who works for CNN was being pelted with peanuts by a convention-goer, who said: "This is how we feed the animals." Read more

Sources

• Gary Younge in The Guardian
• Image: Breaking News

Gary Younge is a feature writer and columnist for The Guardian based in the US.

His vice-presidential choice is well-known for his pro-life advocacy and his conservative economic views.

Explaining his pro-life position, Ryan has said: "I cannot believe any official or citizen can still defend the notion that an unborn human being has no rights that an older person is bound to respect."

As for his economic views, he was architect of a federal budget condemned by Catholic bishops as failing a "basic moral test" in that it slashed food assistance to the poor and radically redefined safety net programmes such as Medicare.

Ryan, 42, contended that the poor are hurt more by extreme levels of government debt than by budget reductions. He defended his fiscal positions against critics in a lecture at Jesuit-affiliated Georgetown University last April. He cited Catholic social teaching principles of subsidiarity and solidarity and charged that "government-centred" approaches to poverty have failed.

Paul Ryan has been criticised for the formative influence of the laissez-faire capitalist philosopher Ayn Rand on his economic outlook. However he has publicly renounced Ayn Rand's philosophy. He said: "It's an atheist philosophy. It reduces human interactions down to mere contracts and it is antithetical to my worldview."

Introducing Ryan as his running mate, Romney declared: "Paul is in public life for all the right reasons — not to advance his personal ambitions but to advance the ideals of freedom and justice; and to increase opportunity and prosperity to people of every class and faith, every age and ethnic background. A faithful Catholic, Paul believes in the worth and dignity of every human life."

Paul Ryan has signed the National Organization of Marriage's pledge to defend marriage as a union of a man and a woman and to seek the appointment of judges who will defend marriage.

Sources:

Catholic News Agency

National Catholic Register

Image: Daily Mail

The "Nuns on the Bus" are focusing on budget cuts proposed by House of Representatives budget committee chair Paul Ryan, a Catholic who has in the past expressed enthusiasm for the views of libertarian author Ayn Rand.

The nuns, a rotating crew of 14 sisters sponsored by the Catholic social justice lobby group Network, say Ryan's plans to cut spending on Medicaid and the Childrens Health Insurance Program would harm "people who are already suffering".

In their big, colourful bus, the nuns are attracting rock-band attention, with video crews from CNN, PBS, CBS and documentary makers following their path.

Since the bus tour dates overlap the US Conference of Catholic Bishops' "Fortnight of Freedom", some observers suggest the nuns aim to divert attention from the bishops' campaign.

This campaign, targeted mainly at President Obama's decision requiring most employers to provide health insurance that includes birth control, has been organised around liturgical feasts for martyred defenders of the faith.

It includes prayer vigils, rallies and other events to draw attention to what the bishops see as government attacks on religious freedom.

Independent advocacy groups such as CatholicVote.org and Women Speak For Themselves, have joined the effort with TV ads, videos, Facebook appeals and petition drives.

Sources

• CNS
• Deseret News
• Washington Post
• Nuns on the Bus
• Image: Nuns on the Bus

Instead, he has performed will among the evangelical Christian voters.

Santorum, who has spoken spoken with a conservative voice on social issues, a man who seeks prayers as well as votes and placed a strong emphasis on family life, received another setback in the strongly-Catholic Puerto Rico primary when Mitt Romney crushed his rivals.

Romney's "Catholic-vote" advantage over Santorum is reported to be above 20 percentage points.

Searching to find out why, the only reason Santorum could pose was the religious fervour of Catholics is less uniform than the evangelicals.

"You know, I really wish I could tell you. The bottom line is that we do well among people who take their faith seriously, and as you know, just like some Protestants are not churchgoing, they are folks who identify with a particular religion but don't necessarily practice that from the standpoint of going to church and the like. And I think folks who do practice their religion more ardently, I think we do well [with them], Santorum told Sandy Rios of American Family Radio.

"Just being Catholic by no means buys you anything in the Catholic vote anymore," said Mark Gray, a researcher at Georgetown University's Center for Applied Research in the Apostolate, who specializes in American Catholics.

Only 20% of Catholics on average said it mattered "a great deal" that a candidate share their religious beliefs, compared with one-third of non-Catholics in exit polls that asked the question.

According the the Pew Research Centre, some Catholics have mistaken Santorum's rather black and white, good and evil, moralistic campaign as one conducted by a conservative Protestant.

Sources

• Huffington Post
• Richmond Times Dispatch
• Image: Huffington Post

A 2008 survey by the Pew Forum on Religion & Public Life found a significant Democratic advantage among Catholics. Fifty-three percent identified as Democratic or leaning Democratic voters, compared to 37 percent identifying with the Republican camp.

That is the moment, three years ago, that Mr. Gingrich says he decided to become a Roman Catholic, after having been born a Lutheran and joining the Southern Baptist Church in college. In 2009, Mr. Gingrich was baptized in the same Catholic parish church on Capitol Hill where Senator Robert F. Kennedy once attended noonday Mass and sometimes assisted the priest as an altar server.

But Mr. Gingrich represents a new kind of Catholic, one very different from the Kennedys, who were Democrats, political liberals and cradle Catholics shaped by the Irish immigrant church.