More than a month before the Washington vote on the nuclear agreement with Iran, President Barack Obama has already secured the support of around 20 Democrat senators.
He needs 34 of them to back him in order to prevent the deal's opponents from reaching a majority that would halt the deal and prevent the removal of sanctions against Iran.
All the indications on Capitol Hill are that Mr Obama will succeed in gaining the necessary votes, but neither side is letting up in its campaign.
The Republican Party, which along with the Israeli leadership is adamantly opposed to the agreement, has been pressuring wavering Democrats alongside intense lobbying from some Jewish-American groups, chief among them AIPAC.
So far, only one Democratic senator, Charles Schumer of New York, has said that he will vote against the deal. He said he was concerned that the agreement would strengthen Iran without preventing it from building a nuclear weapon.
The Obama administration, despite its expressed confidence that it could push the deal through Congress, has nevertheless aggressively attacked its opponents. President Obama accused the Republicans of making "common cause" with the Iranian hardliners who also opposed the deal.
Mr Schumer received abuse following his comments. White House aides questioned whether he could become the Democrats' leader in the Senate next year and a former adviser to Mr Obama accused him of wanting "war with Iran".
The Jewish senator was swamped by online antisemitic abuse
that questioned his loyalty to the US.
