Adli Hakimi knows the first obstacle in Johor’s state election is not the ballot box, but the Causeway. The 26-year-old nurse is among Johor’s workers based in the city state – often called “SGD fighters” online for earning stronger Singapore-dollar wages – who are weighing leave, shifts and border queues before polling day on July 11. For Malaysia, the challenge is keeping immigration glitches and Causeway congestion at bay so that these voters can take part in one of the country’s most closely...