As Turkey’s June 7 general elections draw near, the fate of the ruling Justice and Development Party (AKP) and President Recep Tayyip Erdogan hinges on whether the Peoples’ Democratic Party (HDP), an offshoot of the Kurdish movement, will overcome the 10% national vote threshold to enter parliament.

The outcome of the HDP struggle with the world’s highest threshold lies at the heart of all scenarios for the AKP, both positive and negative. One of the best scenarios for the ruling party is to clinch a three-fifths parliamentary majority, or at least 330 of the 550 seats, which would allow it to rewrite the constitution unilaterally in line with Erdogan’s ambitions for an authoritarian executive presidency and take the draft to a referendum.

Due to the intricacies of Turkey’s electoral system, the HDP’s failure to pass the threshold and enter parliament would mean a huge boost for the AKP, as it would take over the seats the HDP would have won in the Kurdish-majority east and southeast, where the ruling party is the HDP’s only rival. Thus, by grabbing the HDP seats, the AKP would have the opportunity to secure more than 330 seats.

This scenario, however, has increasingly waned over the past several weeks as almost all opinion polls point to a decline in AKP support. The party, which won 49.9% of the vote and 326 parliamentary seats in the 2011 polls, is now down in the 40-42% range. This means the AKP would fall short of 330 seats even if the HDP flops at the threshold and loses its seats to the ruling party.