It's often the little elections that have been the most deadly in Mexico. And nothing has changed this year.

As Sunday elections grow near in 14 states, at least eight local politicians or their family members have been killed. Others report being kidnapped or shot at.

The causes of most of the attacks are still uncertain. Some fear that drug gangs are asserting their power. Some fear a few local politicians themselves are turning to violence. But it is clear that people are being attacked for seeking office.

Mexican President Enrique Pena Nieto has portrayed a nation of vigorous democracy where violence is down and the economy is improving. But the killings show that at the grassroots level, many of the nation's old ills remain.