A supporter of Brazilian presidential candidate Jair Bolsonaro is seen in front of the Bolsonaro's condominium at Barra da Tijuca neighborhood in Rio de Janeiro, Brazil October 5, 2018. REUTERS/Sergio Moraes

SAO PAULO/BRASILIA (Reuters) - Brazil’s far-right presidential candidate Jair Bolsonaro has widened his lead over leftist Fernando Haddad ahead of Sunday’s election, and would win a likely second-round run-off later this month, a CNT/MDA poll showed on Saturday.

Bolsonaro’s support grew to 36.7 percent from 28.2 percent in the previous poll, while second-placed Workers Party candidate Haddad slipped to 24.0 percent from 25.2 percent. Bolsonaro’s share of valid votes surged to 42.6 percent from 35.3 percent, suggesting that with further growth he could even win a majority of votes on Sunday, and avoid the Oct. 28 run-off.