NPR News Now covers the midterm election outlook, noting that while Democrats lead nationally, polls show much tighter margins in key competitive House races. The report also details Alaska Senate candidate Mary Peltola rescheduling events after a minor car accident and highlights a major political shift in Serbia, where a student-led list defeated the party of long-time leader Aleksandar Vucic. Additional stories include Nobel laureate Maria Corina Machado’s return to Venezuela, new research linking climate change to 50,000 heat-related deaths in Europe, and box office results for the film…