Eight years after its introduction, the electoral authority (TSE) has used its power to revoke the electoral victories of candidates who buy votes 215 times. Estadao.com writes that 101 of these were mayors, 53 were vice-mayors, and 51 were councilmen. The small remainer were federal deputies, senators, or governors. Some politicians, including 25 federal deputies, are currently being investigated. The article also notes that the rate of penaltization has increased throughout the years.
There are many thousands of political candidates just in federal elections alone, but given that the 215 penalties are only politicians that got caught and only politicians who had been elected, it would not seem that the law itself is much of a deterrent to vote buying.
The figures would also seem to indicate that vote buying predominates at local levels, but this may not be the case. It may be that such instances are easier to detect at the local level, or they may be easier to detect in contests where there is a single seat at stake. In elections to the federal Chamber, by contrast, up to 70 seats may be allocated simultaneously in large proportional representation districts where literally hundreds of candidates run. In these elections, political competitors may not be able to monitor one another, and thus detection may be more difficult.