MEXICO CITY - It's often the little elections that have been the deadliest in Mexico. And nothing has changed this year.

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

The causes of most of the attacks are uncertain. Some fear drug gangs are asserting power. Some fear a few local politicians themselves are turning to violence.

But it is clear that people are being attacked for seeking office in legislatures and municipalities where organized crime often rules and where old-style, iron-fisted old pols sometimes still try to control the vote.

President Enrique Peña Nieto portrays a nation of vigorous democracy where violence is down and the economy is improving. But the killings show that at the grass-roots level, many of the nation's old ills remain.

"It seems to me that the violence is a little higher this year, though we don't have reliable statistics," said Jeffrey Weldon, political scientist at the Mexico's Autonomous Institute of Technology. "Violence affects democracy and is damaging democracy in Mexico, if no one can run for their party safely."

The cases seem to have accelerated over the past week, and politicians from throughout the political spectrum have been targeted ahead of the vote for 931 mayors, 441 state representatives and one governor.

Most of the killings have been in rural areas heavily hit by drug violence. Cartels are known to interfere in local campaigns to elect officials friendly to their interests. Rural Oaxaca, scene of two attacks, is well-known as a place where disputes over land and resources lead to violence.

In past decades, much of the country's political violence was blamed on Peña Nieto's Institutional Revolutionary Party, or PRI, which frequently used heavy-handed tactics to keep power for 71 years.

The attacks seem to undermine suggestions by Peña Nieto's government that the country may have turned the corner on a surge of violence over the past decade. Before last year's presidential vote, many suggested that the PRI might reduce the killings by returning to the old practice of finding a way to coexist with criminal groups, tacitly or otherwise.

"Everyone has the notion that the PRI is going to be able to restore order in Mexico," said David Shirk, director of the University of San Diego's Trans-Border Institute. "But here you have party candidates or members of the campaign coordination being killed. They're not able to prevent violence from happening."

"It seems to me that the violence is a little higher this year, though we don't have reliable statistics."

Jeffrey Weldon,

political scientist at Mexico's Autonomous Institute of Technology