Noting that over the course of the campaign he never once heard any misgivings in Israel about the heavy involvement of a foreign leader on the prime minister's behalf, Mr. Alpher adds, "Trump is very popular here".
Trump told reporters at the White House that Netanyahu's re-election improved the chances of peace between Israel and the Palestinians.
Netanyahu's pledge was widely seen as an appeal to the far right, and it appears to have worked: He boosted the number of parliamentary seats for his Likud, while smaller, far-right parties struggled. As long as he remains in power, Netanyahu has leverage in talks with coalition partners - although his need for protection also empowers other parties as they try to forge a government.
Two weeks before the election, Trump signed a proclamation, with Netanyahu at his side at the White House, recognising Israeli sovereignty over the occupied Golan Heights captured from Syria in the 1967 Middle East war.
It was not clear what he meant.
Netanyahu tweeted that Trump had called him from Air Force One.
The election was seen as a referendum on the veteran prime minister, who has built a reputation as guarantor of Israel's security and economic growth, but whose divisive right-wing populism and alleged corruption led to calls for change.
Hanan Ashrawia-a member of the executive committee of the Palestine Liberation Organization (PLO)-pointed to Netanyahu's annexation threat as one of many reasons to be alarmed by the prime minister's reelection and the victory of the Israeli right.
But the United Torah Judaism party representing Ashkenazi ultra-Orthodox Jews, won seven seats, one less than in the preliminary results, meaning that the right-wing and religious bloc still commands a total of 65 seats.
Final official results are expected to be announced by Friday. "Palestinian leadership has been unwilling to accept any reasonable peace proposal or even to negotiate seriously toward a solution".
Rivlin's office said it would take the "pioneering and historic" step of broadcasting the president's discussions with party leaders live "in the name of transparency".
"We respect the decision of the people", Gantz said on Wednesday night.
The main rival of Netanyahu's party - the Blue and White alliance (led by Benny Gantz and Yair Lapid) - secured 35 seats. Only a big push in the final hours of voting secured the survival of the two primary Arab parties in Parliament.
In addition, Netanyahu himself, in his eagerness to rally votes, has made promises that he will find hard to keep without also endangering national interests.
"It is a night of colossal victory", the 69-year-old Netanyahu told cheering supporters in a late-night speech at Likud headquarters in Tel Aviv after Tuesday's vote.
Netanyahu had run in the polls while facing corruption and bribery charges in three cases. There is an emerging argument among Democrats on whether to become more sharply critical of Israel under Netanyahu.