Mexicans headed to the polls on Sunday to vote for a new lower house of Congress, state governors and local lawmakers, in a race seen as a referendum on President Andres Manuel Lopez Obrador’s policies and shakeup of Mexico’s institutions. All 500 seats in the lower house, 15 state governorships and thousands of local leadership positions are up for grabs, with some 93.5 million Mexicans eligible to vote. The election has been tinged by the...