Mario Monti, a straight-laced Catholic professor who is the outgoing technocrat prime minister, should be an obvious favourite for the Vatican in Italy's elections this weekend.
But his likely alliance with the very secular centre-left gives the Church pause.
The Catholic vote is not to be ignored in Italian politics; only comedian Beppe Grillo has openly derided the Church and rejected its opinions.
All the other contenders in the elections Sunday and Monday have lined up to express their respect for Pope Benedict XVI, whose abrupt announcement that he will retire at the end of the month has shaken the world's smallest city state lying across the Tiber.
The Catholic vote is divided between the centre-right of Silvio Berlusconi, the centre-left of Pier Luigi Bersani and supporters of Monti, who is standing in the polls at the head of a "Civic List".
The Vatican newspaper L'Osservatore Romano broke protocol in December by endorsing Monti, a practising Catholic.
The head of the Italian Catholic Church, Cardinal Angelo Bagnasco, who has been highly critical of Berlusconi, has also praised Monti, a former European commissioner, and his economic reforms.
Vatican expert Sandro Magister says that Andrea Riccardi, the founder of the Catholic Sant'Egidio movement who is now Italy's international cooperation minister, "had a direct influence" on Monti's decision to throw his hat in the ring.
Magister told AFP that Sant'Egidio -- which is known mainly for brokering peaceful resolutions to international crises -- has built "a true rapport of confidence with the pope" through Georg Ganswein, the pontiff's personal secretary.
Monti has met the pope eight times since forming his technocrat government in late 2011 after Italy's economic crisis ushered Berlusconi out of power.
But the Church has cooled towards Monti at the approach of the elections.
"The bishops have back-pedaled a bit," said Andrea Tornielli, an expert who writes for the Vatican Insider website.
The Italian weekly L'Espresso says that, unlike Bagnasco, Vatican number two and secretary of state Tarcisio Bertone still backs Berlusconi because he is "the only one who has had the courage (to back) non-negotiable values" such as opposing euthanasia even in the most extreme cases.
Bertone "prefers to talk to a patented sinner than a boring moralist," L'Espresso wrote.
But other Vatican prelates, L'Espresso says, have been disappointed at Monti's reluctance to defend traditional Christian values such as pro-life positions and the family.
They have moderated their support in view of a probable alliance between Monti and Bersani's Democratic Party, which is in step with Italy's changing society.
The Vatican dropped Berlusconi and his faltering government like a hot potato in 2011 after one sex scandal too many.
In a first last year, the Vatican made a concession to the Monti government that it would pay more taxes on its enormous property holdings.
A movement to create a new Catholic party to replace the old Christian Democrats, who folded in the 1990s after a vast corruption scandal, failed for lack of unity and a strong enough following.
Meanwhile the Catholic Church has been steadily losing sway among Italians, notably on the issues of divorce, gay marriage, abortion, euthanasia and bioethics.
The Eurispes think tank says Italian politicians pay more attention to Church dictates than the electorate. Support among Italians for euthanasia in cases of extreme suffering jumped from 50 percent in 2011 to nearly 65 percent last year, Eurispes said.