RIO DE JANEIRO, Rajab 07, 1437, April 14, 2016, SPA -- President Dilma Rousseff's chances of surviving impeachment appeared diminished Wednesday, with three parties decamping from her governing coalition in 24 hours as Brazilian legislators prepare for a crucial vote on the question expected this weekend, according to AP. The pullouts of the mid-size centrist parties sparked growing despondency among members of Rousseff' left-leaning Workers' Party ahead of the vote expected Sunday in the Chamber of Deputies. That vote will determine whether the impeachment process moves ahead based on allegations that Rousseff's administration violated fiscal rules. The pro-impeachment camp needs two-thirds of the 513 votes in the lower house, or 342 votes, to send the proceedings to the Senate for a possible trial. According to a tally by the newspaper Folha de S. Paulo, 284 legislators have come out for impeachment, while 114 are opposed and 115 are undecided. --SPA 02:09 LOCAL TIME 23:09 GMT www.spa.gov.sa/w