SAN LUIS RIO COLORADO, Son. - Voters in this border city go to the polls Sunday to elect candidates in races for three-year terms of office for mayor, Sonora governor and state and federal legislators.

More than 134,000 residents of San Luis Rio Colorado and surrounding communities that fall under that city's jurisdiction are registered to vote.

During voting, sales of alcohol at bars, restaurants and liquor stores will be suspended under Mexico's ley seca, or dry law.

Running for mayor are Ángel Ruiz García of the National Action Party, Manuel Baldenebro Arredondo of the Institutional Revolutionary Party, Manuel Santeliz of the Democratic Revolutionary Party and Santos González Yescas of the Workers Party.

The National Action Party, known by the Spanish acronym PAN, has won the mayorship in successive elections since 1994. It is the party of Mexico's current president, Felipe Calderon.

Running for governor are the centrist Institutional Revolutionary Party's Alfonso Elías Serrano, the PAN's Guillermo Padres Elías and the leftist Democratic Revolutionary Party's Petra Santos Ortiz.

The Institutional Revolutionary Party, PRI, currently holds the governorship. The PAN has never won a governor race in Sonora, though some observers think it could this year.

The PRI, founded in 1929, had dominated government at all levels in Mexico before its candidate lost the presidential election to the PAN's Vicente Fox in 2000. Calderon was elected in 2006.