Yair Lapid has yet to announce the establishment of his new party but some polls are already predicting that over 15 per cent would vote for it were elections to be held this week.
Mr Lapid's resignation on Sunday from Channel Two, where he presented the flagship weekly news magazine Ulpan Shishi ("Friday Studio") was his first tacit admission that he is planning to run in the next Knesset elections.
Mr Lapid, 48, a broadcaster, journalist and author, has been expected to take the plunge into politics for the past few years, but the timing of his move this week was hardly advantageous.
This month, the Knesset is expected to introduce a law mandating a year's "cooling-off" period for journalists before they can run for office. Since Prime Minister Benjamin Netanyahu is expected to bring the elections forward to this autumn, such a law would prevent a Lapid candidacy.
Despite being forced to relinquish his prime-time slot prematurely, Mr Lapid was not giving any interviews this week, preferring to officially launch his campaign closer to the elections.
Instead, he communicated this week via Facebook, writing that he was "embarking on a new journey, equipped mainly with the strength derived from the fact that I am doing something I believe in".
The son of the late Yosef "Tommy" Lapid, who also turned to politics after a career in the media, Mr Lapid started writing 30 years ago for the IDF magazine Ba'machane. Since then, he has turned his hand to almost every possible creative pursuit, writing poetry, song lyrics, plays, novels and TV series. Above all, however, he has been the most widely-read columnist on Israel's top-selling tabloid Yediot Ahronot, and on television, the presenter of prime-time talk shows. For years he was a regular fixture on the "sexiest man in Israel" lists but he set tongues wagging four years ago when he gave up lucrative advertising contracts to go into "serious" journalism and became anchor of Ulpan Shishi. That was when the speculation over his political aspirations began in earnest.
Although he is yet to release an official manifesto, Mr Lapid has been publishing his blueprints for Israel's future in his columns and, if they are anything to go by, his new party will sit in the middle of the political spectrum. A number of prominent candidates are already in talks with Lapid on joining his party, including two former IDF generals, the mayor of Herzliya and a popular modern Orthodox rabbi.
● Noam Shalit, father of former PoW Gilad Shalit, announced on Monday he would be running for the Labour Knesset list. On Tuesday, Mr Shalit, a party member since 1996, said: "Israeli society helped us in our hour of need… Today I want to contribute to society."