Likud leaders put heavy pressure on party activists to attend the rally.
Party leaders described it as an attempt to counter a vicious campaign by a hostile media and overzealous police and state prosecution.
And in an effort to raise the party's morale, Mr. Netanyahu also spoke of Israel's growth and achievements during his tenure over the past eight years. Mrs Netanyahu has denied all the allegations against her, but the police recommended indicting her previous year, and the attorney-general is close to doing so, according to a report on Channel 2, the Israeli TV channel.
Netanyahu got bad news last week with the news that former chief of staff Ari Harow, in trouble over his own private business dealings, agreed to cooperate with investigators against the prime minister, reports the New York Times.
Netanyahu has repeatedly denied corruption allegations and any wrongdoing, calling the claims a "witch hunt" initiated by the media. He is also accustomed to access to the inner sanctum of Israeli politics, having enjoyed close relationships with former premiers Shimon Peres and Ehud Olmert and serving as emissary between them, as well as Netanyahu, with various bold-faced names in Hollywood.
Netanyahu's four terms as Israel's prime minister haven't of course been free from scandals.
"This is not new; they have been trying for many years to topple the right-wing", he said.
But Professor Gadi Wolfsfeld, who teaches political communications at the Interdisciplinary Centre in Herzliya, said the notion that there is nobody to replace Mr Netanyahu holds "until it happens".
"The media has mobilised in an obsessive campaign against my family and me, but you the voters are the ones really targeted. the people are with us", he told the crowd.
Israelis have been demonstrating against Mr. Netanyahu on Saturday evenings near the home of the attorney general, Avichai Mandelblit, in the town of Petah Tikva in central Israel. All of the ministers and Knesset members from the Likud party have made an appearance, declaring their continued support for the prime minister.
No one in the party has come out against Netanyahu yet - reflecting both loyalty and the fear of crossing him.
When the investigations conclude, police will hand the matter over to the attorney general. But some politicians have said that he shouldn't necessarily step down even if he's indicted. "The whole point it to scare any of the "pretenders" against getting ideas in their head".
Netanyahu, who is not under investigation in the case, has given his full backing to his lawyer.
It is alleged that he received lavish and "inappropriate" gifts from wealthy supporters such as cigars and champagne, and offered commercial favours to Yedioth Ahronoth newspaper owner Arnon Mozes in return for positive coverage.
Netanyahu has escaped several scandals before, but the scope of the latest accusations appears to pose his stiffest challenge yet.
Netanyahu has dismissed the suspicions as "background noise" and vowed to push forward.