The road from Caracas to Guatire is lined with propaganda billboards glorifying President Nicolás Maduro and likening his political rivals to gangsters from the country’s most infamous criminal group. “They won’t defeat us,” the slogan declares.

But with less than a month until the economically fractured South American country holds its long-awaited presidential election on 28 July, some people are not persuaded.

“Yes we can! Yes we can!” opposition supporters chanted as they gathered in this city on the eastern outskirts of the capital to champion the duo hoping to end the 11-year rule of Hugo Chávez’s unpopular heir – and more than a quarter-century of Chavismo.

The two politicians in question are María Corina Machado,…