With barely more than a month under her belt as a professional politician, Yingluck Shinawatra stood poised Monday to become Thailand’s first woman prime minister after her Pheu Thai party scored a resounding victory in Sunday’s national elections. Riding a well-oiled political machine and benefiting from the popularity of her brother, Thaksin Shinawatra, who was deposed as prime minister in a 2006 military coup, Yingluck and her party won an apparent majority in parliament according to unofficial election returns.