For nearly two decades, the military and conservative establishment in Thailand has sought to keep former Prime Minister Thaksin Shinawatra and his supporters out of power. Thaksin, a populist politician and a business tycoon, was ousted in a coup in 2006 before he fled the country. Several years later, his sister succeeded him as prime minister and then suffered the same fate.

Now, conservatives are watching warily as his political party looks set to dominate next month’s election. The party’s star campaigner is Paetongtarn Shinawatra, Thaksin’s youngest daughter and a strong contender for prime minister.

With a formidable last name but little in the way of political experience, Paetongtarn, 36, has revived the prospect of her father’s return from exile and the resurgence of the most politically polarizing dynasty in Thai politics. Critics have tried to seize on her family’s past scandals — and on her current pregnancy, eight months along — but she has galvanized crowds during campaign events and fueled nostalgia for her family’s legacy.