The main headline from Sunday's polls is expected to be the hammering of the leftist Workers' Party, which many here blame for Brazil's punishing recession and sprawling corruption scandals.
Already reeling from the impeachment of former president Dilma Rousseff and her replacement by center-right rival Michel Temer, the once-dominant Workers' Party looks set to lose a slew of local seats, including the mayor of Brazil's biggest city Sao Paulo.
But analysts say that a recent spate of killings around Brazil points to a darker political shift.
He was shot dead, along with a police officer, while campaigning yesterday, Globo news site reported. The state's deputy governor was also wounded in the attack in which the gunman was killed by security guards.
Also Read
Worries about violence have prompted deployment during the election of extra army and elite police forces to 266 municipalities in 11 states, according to Globo.
The main hotspot is Rio de Janeiro, where 15 candidates or politicians have been murdered over the last 10 months, police say.
His execution-style slaying remains unsolved but Brazilian analysts and media quickly linked it to shadowy armed groups known as militias.
De Souza, who headed one of Rio's biggest and richest carnival samba schools, was also a police officer and had been cleared of militia-related charges back in 2011.
Another candidate for municipal government -- Jose Ricardo Guimaraes, who headed a private security firm -- was shot dead the previous day at a rally in Itaborai, also in metropolitan Rio.
Disclaimer: No Business Standard Journalist was involved in creation of this content