One overlooked aspect of Benjamin Netanyahu’s last minute victory leap in the 2015 election is that it could’ve been an even more decisive victory for the right-wing bloc of parties if it were not for one fact: the stubborn determination of former Interior Minister and Shas chairman Eli Yishai to run on his own ticket, Yachad. Ahead of the election Yishai, along with former Bayit Yehudi MK Yoni Chetboun, joined forces with the far-right Otzma LeYisrael party led by Baruch Marzel, a nationalist and religious extremist who was once an active member of Meir Kahane’s outlawed Kach Party.

The reasoning behind the alliance was clear enough, even if it looked bizarre. Yishai, while conservative, by no means had a reputation of being righter-than-thou; in fact, according to Netanyahu biographer Ben Caspit, he played a key role in scuttling Netanyahu and Defense Minister Ehud Barak’s plans to strike Iran’s nuclear program in 2009-2010. Yishai was also willing to entertain a center-left government. By most accounts he negotiated honestly with Tzipi Livni prior to the dissolution of the Olmert government in 2008, but she instead opted to go to elections.

The merger was born out of convenience and it was arguably essential for both sides: Otzma had failed to win seats in the 2013 election and a disgruntled Yishai had recently been replaced as Shas leader by Aryeh Deri, a former party chief and the current interior minister. Alone, neither Yishai nor Otzma had enough support to cross the electoral threshold in 2015, which had increased from 2 percent to 3.25 percent.

The end result was a significant loss for the entire right bloc. Yachad failed to cross the electoral threshold, and took over 125,000 right-wing votes down with it (around 3 percent of the total number cast in the election). To put this number in perspective, Meretz secured five seats in the Kensset with around 165,000 votes. It’s true that Marzel would probably not have been welcome in a Likud-led coalition (or so we should hope), but Yishai is a dealmaker who could’ve brought along 2 or 3 more MKs in the coalition, which was initiated with a one-seat majority in May of 2015.

In the right bloc itself, the party most affected was obviously Shas, which had its worst result since 1992, finishing with 7 mandates. Had Yishai crossed the electoral threshold, Deri would’ve been doubly humiliated.

According to almost all recent polls, if an election were held today, Shas would emerge with 4 or 5 seats, which when you consider the volatility of Israeli elections calls to mind the macabre aphorism of having “one foot in the grave and the other on a banana peel.” This is not a position any party, let alone one accustomed to serving as a lynchpin for coalitions left and right, wants to find itself in.

Shas is desperate and is acting as such. Yishai, who has few friends remaining in the Shas leadership after his devastating betrayal, is receiving overtures from his old party. According to a report in The Jerusalem Post last week, Shas offered Yishai a ministerial position in the next government if he shuttered Yachad. Yishai reportedly rejected this offer, instead countering with a proposal that Shas and Yachad run on a joint ticket, a scenario which perhaps makes political death look rather appealing to Deri.

Another factor, however, makes the situation even more dire for Shas: the emergence of Orly Levy-Abekasis as a political force. The daughter of David Levy, a former foreign minister who still commands admiration among some Mizrahi voters, Levy-Abekasis’s unnamed party has polled between 4 and 8 seats in recent weeks. While her focus on socioeconomic issues is seen as most threatening to the center-left bloc, the nationalist camp is starting to worry as well: Netanyahu apparently does not believe that she will recommend to President Rivlin that he form the next government. As a right-leaning party that relies on the votes of poor and historically marginalized communities that have become more politically independent in recent years, Shas is especially vulnerable to a new boutique outfit like Levy-Abekasis’s – and it doesn’t have to lose many voters to find itself excluded from the next Knesset.

If Shas disappears from the scene, the potential consequences for each bloc are huge. It will give the right less breathing room (without Shas now, Netanyahu would be forced to seek an agreement with one of the opposition parties) and make the path for the center-left to return to power even more daunting. Haredi representation in the Knesset will be entirely Ashkenazi and weakened.

Israel-watchers are used to seeing new parties, even large ones like Kadima, decimated quickly after their initial rise. While Shas has not existed since the establishment of the state, its demise would represent an unprecedented fall for an established player of the modern era. Israeli politics will not be the same again.