ROME (AP) — How much weight does an endorsement from a lame-duck pope carry in the upcoming election?

No, not that election — the one to pick the next leader of the Catholic church. Another key ballot is looming even closer, when Italians go to the polls this Sunday to choose a new premier. And with Italy in a solemn mood over the historic resignation of Benedict XVI, the "moral vision" of incumbent Mario Monti may get a boost to the detriment of the flamboyant, scandal-plagued Silvio Berlusconi.

Even though a large majority of Italian Catholics don't regularly attend Sunday Mass, the Vatican traditionally wields influence on politics in Italy, a country where Christian Democrats held sway for decades. Just about anything the pope does or says is big news. And Pope Benedict XVI has made no secret of his preference for Monti, a practicing Catholic, whom he greeted warmly on Saturday in one of his last private audiences with an Italian political leader.

On the other hand, the Vatican has expressed its horror over the string of sex and corruption scandals swirling around the billionaire media mogul Berlusconi. And with the dignity of the papal transition very much on Italian minds, Benedict's clear preference for Monti could be a factor in making voters think twice about backing a figure who has become synonymous with an amoral, me-first way of life.

Experts do warn: Don't expect the papal factor to sway the election. But it's clear that the candidates may be adjusting their rhetoric to the spirit of the times.

Frontrunner Pier Luigi Bersani, who as a veteran of Italy's left espouses a more secular kind of ethical vision, hammered away at the issue of "morality" at a campaign rally Sunday in the critical region of Lombardy. While he comes from a different political tradition from the center-right Monti, the two share an emphasis on economic reform that could very well make them a good match in a future coalition government.

Italian law bans publication of opinion polls in the last two weeks before elections, so it's hard to tell if the sudden focus on religious affairs has caused undecided Catholics to shift toward Monti, the only practicing Catholic among the main candidates.

But a photo op with the pope is Italian candidate heaven, and Monti, because he is premier, got the providential tete-a-tete with Benedict as part of the pontiff's farewells. That Benedict carved out time in the waning days of his papacy to chat privately with Monti reflected both the importance accorded to the relationship between Italy and the Holy See, as well as the Vatican's own preference for Monti.

On Saturday evening, as cameras clicked and rolled, the outgoing pope and caretaker premier grasped hands and smiled warmly at each other in the ornate Apostolic Palace.

If Monti's rivals fumed, they did so in private.

Milan daily Corriere della Sera wrote of the Benedict-Monti farewell that no politician dared to publicly grouse that their rival was getting an unfair boost for fear of "a boomerang" effect from devout Catholics.

Still, "the parties' silence doesn't erase the annoyance felt in some quarters for an appointment on the cusp of the vote," Corriere wrote.

Bersani's Sunday rally, his last of the campaign, included a surprise speaker, ex-premier Romano Prodi, a practicing Catholic who has defeated Berlusconi in the past and was viewed favorably by the Vatican when he twice governed Italy. Coincidence? Or calculated catch-up?

Monti, an internationally respected economist, clearly has the Vatican's blessing.

When, on Christmas Day, Benedict urged Italians in greetings to the crowd in St. Peter's Square to reflect on a "hierarchy of values" when making important choices, the country's media interpreted the papal message, pronounced from the central balcony of St. Peter's Basilica, as a virtual endorsement of a second Monti term.

Three days later, Monti announced he was heading an election coalition made up of centrists, business leaders and other pro-Vatican forces that back his "ethical" vision of politics.

In late January, a poll commissioned by Italian Catholic weekly Famiglia Cristiana found more than one-third of practicing Catholics surveyed were undecided, largely in line with the percentage of undecided Italians across the board. But the same poll found that a good deal of Monti's support comes from practicing Catholics.

Overall, polls have indicated Monti would need a miracle to finish first. But he is well-positioned to win enough votes to be the kingmaker for a new coalition, in which he could then be expected to wield sizable influence.

Benedict made no public comments about his final audience with Monti. But the Vatican said that the two shared a "particularly cordial and intense encounter." The pope will also see Italy's president, but not until after balloting ends.

"Any coverage is good for Monti," said James Walston, a political science professor at American University of Rome, about the possible effect of the papal audience.

Even political analysts who doubt the Catholic church carries much weight with Italian voters agree that major candidates keep Catholic sensibilities in mind.

"A political party in Italy, given we are in Italy, with its religious traditions, with the historic presence of the church, tries not to appear anti-Catholic," said Pietro Grilli di Cortona, a political science professor at Rome's Roma Tre, a state university.

When beset by an earlier sex scandal, even Berlusconi tried to sound pious in a pitch to Benedict in hopes of a political boost.

In 2009, during his third stint as premier, amid reports of a dalliance with a high-end prostitute, Berlusconi wrote a Christmas letter to Benedict asserting that Christian values guide his government's work.

And while Bersani cut his political teeth in Italy's now defunct Communist Party, his coalition includes several former Christian Democrats.

In Bersani's coalition, said Walston, "there's a strong element of Catholics."