Hamas leaders received Arab and Turkish foreign ministers in Gaza on Tuesday, following similar trips by Egypt's prime minister and Tunisia's foreign minister, as well as one by the emir of Qatar last month before the eruption of a week-old conflict that now seems to be heading into a ceasefire.
"These diplomatic gains strengthen Hamas's argument that it is an integral part of the future of the region, while the Palestinian Authority is part of the past," said Ghassan al-Khatib, an academic and a former spokesman for Abbas's PA.
Western leaders still shun Hamas, which seized control of Gaza from Abbas's Fatah movement in 2007 after winning Palestinian parliamentary elections a year earlier.
Yet while a visit to Ramallah, near Jerusalem, by U.S. Secretary of State Hillary Clinton on Wednesday will acknowledge Abbas's formal status, it can hardly disguise his near absence from the diplomacy that is going in to halting the war in Gaza.
"It simply accentuates how irrelevant Abu Mazen is in regard to the Gaza Strip," Israeli Deputy Foreign Minister Danny Ayalon said on Israel Radio, using Abbas's familiar name.
Mediation efforts have focused on Egypt, whose new Islamist leaders are seeking a ceasefire, juggling their sympathy for Hamas with the practical need not to upset Cairo's peace treaty with Israel or alienate the United States, its main aid donor.
Hamas leader Khaled Meshaal, unwelcome in Hosni Mubarak's Egypt, is now in favor in Cairo, where he demanded that Israel make the first step if it wanted a Gaza truce. "Whoever started the war must end it," he told a news conference on Monday.
President Barack Obama, while shunning Hamas leaders deemed terrorists by Washington, spoke three times to Egypt's President Mohamed Mursi in the day leading to Tuesday's truce move, the White House said. He appeared not to have called Abbas at all.
The spotlight on Hamas's unequal military struggle with Israel has also upstaged a diplomatic initiative that Abbas plans to take to the United Nations General Assembly this month.
And demonstrations in solidarity with Gaza have broken out in Abbas's West Bank fiefdom in the last few days, in which two people were reported killed, testing the PA's security grip.
"The Gaza confrontation is having a radicalizing effect in the West Bank," Khatib said. "It is embarrassing the PA, which is having difficulty in preventing the growing protests. If these expand, it will be at the expense of law and order."
Anger at Israel's assault on Gaza, directed at rockets fired from the densely populated enclave, does not mean pro-Hamas fervor is sweeping the Israeli-occupied West Bank, where economic discontent has already hurt Abbas's waning popularity.
The mood in Ramallah was subdued on Tuesday, with no pop music blaring from shops or young men's cars, as the Gaza death toll climbed beyond 115. Three Israelis have also been killed.
"People don't feel increasing support for Hamas per se, but when they heard Hamas rockets had landed in Tel Aviv, they felt someone was finally doing something to challenge the Israelis," said Ahmad Sliman, 24, at a Ramallah coffee shop where he works.
"It gave people hope that we are not completely defenseless."
Gaza militants have fired at least four rockets towards Tel Aviv since the start of the seven-day conflict, but the missiles have either missed their target or been shot down by the Iron Dome interceptor system, the Israeli military said.
Shireen Yehiya, 26, a student working on her thesis, agreed that Hamas rocket-firing was seen as more defiant than the quest for "futile" negotiations pursued by Abbas's Fatah movement.
"But in the end I think most Palestinians in the West Bank are against the idea of imposing Hamas's religious ideals here."
In the Gaza Strip, people were predictably more scathing about Abbas's non-violent approach, which has calmed the West Bank but brought Palestinians no closer to their dream of statehood.
"Talks and security cooperation with our enemy is always a failure for the Palestinian people, but it is a greater shame when Israel is slaughtering us in this way," said Imad Abu Shaweesh, 40, a mustachioed bank employee in the city of Gaza.
Abbas himself has said the Gaza violence is designed to scupper his plan to ask the U.N. General Assembly to grant the Palestinians non-member observer state status. But he has vowed to press on.
The 77-year-old president has few other options and his initiative, following last year's failed attempt to get the U.N. Security Council to recognize Palestinian statehood, offers at least a slim hope of getting his cause back on the world agenda.
"Negotiations are at a dead end," said Palestinian analyst George Giacaman, arguing that Abbas could try to galvanize the United States and European Union into a serious search for peace only by taking a pugnacious diplomatic approach.
For example, as a U.N. observer member, the Palestinians could press for Israelis to be prosecuted for war crimes at the International Criminal Court in The Hague.
Giacaman said Abbas had been sidelined by the Gaza campaign, but could regain the initiative by "implementing a political form of resistance, a confrontational route with Israel".
Israel has berated Abbas's plan as "diplomatic terrorism" and its finance minister has threatened to stop collecting taxes for the PA and not hand over any money if he persists. The United States says only direct talks with Israel, not maneuvers at the United Nations, can produce a Palestinian state.
Yet two decades of on-off U.S.-sponsored negotiations, punctuated by bouts of violence, have failed. Many Israelis and Palestinians say the goal of a two-state solution is no longer viable. For hardliners on both sides, it is not even desirable.
The last direct negotiations between Israel and Palestinian leaders in the West Bank broke down in 2010 over the issue of Jewish settlement building. Hamas does not recognize Israel, although it has indicated willingness to accept a long-term truce with the Jewish state if it returned to pre-1967 borders.
Abdullah Abdullah, a senior Fatah official, said this means that Hamas shares much with Fatah politically, although its Islamist ideology contrasts with its rival's secular approach.
"Resistance is not only firing a gun, there are many forms of resistance," he said, noting the high price in lives and destruction Palestinians had paid for armed struggle before.
Such talk cuts little ice in Gaza, despite the Israeli battering it has endured for the past week.
"Abu Mazen is a weak political personality. U.N. membership won't change anything on the ground for us, so why bother with this game?" asked Rami Daoud, 37, sipping coffee in his guard post at a construction site. "It's time he left the scene."
For him, Hamas had brought a sense of pride and dignity. "They act like a state. They don't just ask other countries for one," he said. "Hamas has taken over. They're in charge now."