But the diplomatic victory will likely be fleeting, with Israel uninterested -- and Biden for now not pressing -- for a full ceasefire in a war that has killed thousands of Israelis and Palestinians and prompted risks of a wider conflict.
Biden, as well as Secretary of State Antony Blinken and senior aides, negotiated through Qatar and Egypt to arrange the deal in which Hamas will free at least 50 hostages and Israel will release scores of Palestinian prisoners, while offering a four-day truce to war-battered Gaza.
Biden's approval rating a year before the 2024 election has sunk to a new low in a recent poll, at least partly due to younger Democrats' criticism of his staunch support for Israel. But his team was quick to highlight the deal.
The outcome was the work of "tireless diplomacy and relentless effort" by the United States, Blinken said in a statement.
Max Boot, a senior fellow at the Council on Foreign Relations, said Biden made decisions based "not on political calculations but on geopolitical ones, as well as his own emotional attachment to Israel."
"The hostage-release deal -- the result of intensive mediation by the United States and Qatar, including by Biden personally -- gives the White House a tangible achievement it can point to," he said in a blog post.
Boot said that Biden's support for Israel gave him more leverage to press Israel to lessen civilian casualties.
Biden under pressure
But critics say that, whatever power the United States may have, it has not used it.
Win Without War, a network of activists seeking a more progressive US foreign policy, said the deal "shows that productive diplomacy is possible and that international and grassroots pressure can work."
"We urge the Administration to continue to leverage its significant power and influence to pursue a lasting ceasefire and an end to this horrific conflict," Sara Haghdoosti and Stephen Miles, leaders of the group, said in a statement.
Israeli Prime Minister Benjamin Netanyahu has vowed no long-term ceasefire and said his goal remains to destroy Hamas, the Islamist militant group that runs the blockaded Gaza Strip.
Hamas on October 7 carried out the deadliest attack in Israel's history, killing 1,200 people, mostly civilians, and taking some 240 people hostage as they ransacked homes, a music festival and other sites inside Israel.
Israel has responded with an overwhelming bombing and ground campaign, leaving much of Gaza in rubble and killing 14,100 people, including thousands of children.
J Street, a left-leaning pro-Israel US advocacy group often critical of Netanyahu, said Biden should use the pause to "set clear red lines and insist on a significant change in the conduct of this military operation."
"President Biden has rightly demonstrated that US support for Israel's security is ironclad. He should also make clear that the US will not provide unbounded support for a war with no limits and no exit strategy," it said in a statement.
Time for a rethink?
Dick Durbin, the number-two Senate Democrat, has broken with Biden by calling for a ceasefire and on the eve of the hostage deal led a letter with 12 Democratic colleagues urging a parallel effort to ramp up humanitarian aid into Gaza.
"We are concerned that increased and prolonged suffering in Gaza is not only intolerable for Palestinian civilians there but will also negatively impact the security of Israeli civilians by exacerbating existing tensions and eroding regional alliances," the senators wrote.
The rival Republican Party has largely refrained from criticizing Biden, seeing as the deal frees hostages including at least three Americans and it was endorsed by Netanyahu, long popular with the US right.
But John Bolton, the hawkish former national security advisor to Donald Trump during his one term, denounced the ceasefire and said that both Israel and the United States should prioritize destroying Hamas, which is backed by Iran's clerical leadership.
"Showing weakness towards Hamas guarantees continued violence by Iran and its many proxies," Bolton wrote on X, formerly known as Twitter.
