Sara Meza is just the kind of voter Venezuela’s opposition could once count on at the ballot box. A 32-year-old teacher, she’s fed up with President Nicolás Maduro’s government. Her salary has fallen to the equivalent of $2 a month with Venezuela’s currency collapse. She struggles to feed her 10-year-old son and is unable to treat the small tumor on her breast because the health-care system is in shambles. Still, Ms. Meza voted for the ruling Socialist Party in recent mayoral elections, fearing that otherwise, she would have lost her state job and benefits—especially the monthly bags of rice, corn flour and other subsidized food she says keeps her family alive. She also plans to vote for Mr. Maduro in the May 20 presidential election

“If I didn’t vote, there would be trouble, I was told,” she said in this arid town near the Colombian border. “They are playing with people’s hunger.” Any government would struggle to win elections while presiding over widespread food shortages, inflation expected to reach 13,000% this year, and an economy falling apart so fast that it will soon be half the size it was five years ago. But the Maduro administration, which has just a 22% approval rating, has developed a broad strategy to prevail through dirty tricks, fear tactics and, crucially, using the lure of food to get the country’s poorest voters to support his administration, pollsters and elections experts in Venezuela say. Last year, the ruling party won three elections for local, state and national bodies.

Food is an enormously powerful weapon in a country where babies die of malnutrition, store shelves are often bare and three-quarters of the population has lost an average of 19 pounds. The grants to millions of poverty-stricken voters might very well ensure his leftist movement runs this country for many years to come.