Presidential candidates in Iran attend joint campaign rally.

Hardline conservatives in Iran see the current presidential election as an opportunity to do away with President Hassan Rouhani whose race against Ebrahim Raisi has recently gotten tight.

An enormous mosque in Tehran housed over 15,000 conservative Iranians Tuesday evening.They mocked Rouhani, chanting farewell: "Bye bye, Rouhani.At the end of the week, Rouhani is gone."

Ebrahim Raisi has gained sweeping momentum approaching election day (Friday) now that his fellow conservative opponent, Mohammad Ghalibaf who currently serves as mayor of Tehran, has dropped out of the race.Mayor Ghalibaf has put his support behind Raisi, which integrates their hardline supporters.

The rally at the mosque in Tehran is the last one scheduled before election day, and the crowd roared sonorously at the prospect of electing Raisi when he was joined by Ghalibaf on stage.As significant a boon as this may be for Raisi, several minor candidates are now dropping out of the race and putting their support behind incumbent Rouhani.

Rouhani stood for unity among otherwise estranged factions four years ago when he ran for his first term.Known as a reformist and centrist, Rouhani won handily enough to need no run-off election against his five opponents in 2013, and a significant part of his legacy thus far is having negotiated the 2015 nuclear deal with the United States, which was a relatively popular deal given that it relaxed sanctions that had initially stymied the Iranian economy in previous years.

The economy remains stagnant now, however, which is believed to be an important factor in Rouhani's difficulties reaching the 50 percent mark in the polls.Raisi and Ghalibaf have both used their platforms thus far to accuse Rouhani of failing to deliver the economic benefits he promised the 2015 nuclear deal would yield.

Rouhani, on the other hand, has gone as far as to accuse the Revolutionary Guard of trying to undermine the nuclear deal in light of their support for Raisi.He pointed to ballistic missile tests in which volatile, anti-Israeli propaganda was indelibly inscribed on them.