YANGON — Soe Thein is a pious man. Every evening he kneels before a Buddhist shrine in his Yangon home to pray for the only woman he believes can lead Myanmar to a brighter future. “I pray for Aung San Suu Kyi’s health and long life,” says Soe Thein, formerly a political prisoner and senior member of Suu Kyi’s National League for Democracy (NLD). “Who could replace her?” Suu Kyi’s role in a reforming Myanmar will be no less essential after her strong performance in Sunday’s historic by-elections, winning a seat in a parliament dominated by the military and the rival party it created. But after two decades in opposition, much of it spent as a prisoner of the former junta, Suu Kyi now faces a slew of unfamiliar challenges. She must find her place in a perhaps hostile lower house while nurturing her crucial relationship with reformist President Thein Sein and managing the expectations of a nation impatient for change after decades of isolation, poverty and military misrule. “Converting people’s expectations into political reality is the big challenge now,” says analyst Richard Horsey, a former United Nations official in Myanmar. “And for a country as poor as Myanmar, that means addressing the plight of families and their ability to put food on the table, educate their children and look after their health.” Just 17 months ago, Suu Kyi was under house arrest and her party outlawed. Sometimes portrayed as stubborn and unrealistic, her rapid journey from prisoner to parliamentarian is the result of a bold and pragmatic engagement with President Thein Sein that remains critical to Myanmar’s reform process. And she has done this, so far, without eroding the adoration and moral authority she commands across Myanmar. During her election campaign, a people who once referred in fearful undertones to “The Lady” lined the streets to shout for “Mother Suu.” “The pace of change has been breathtaking,” says Robert Cooper, counselor to the European Union’s foreign policy chief Catherine Ashton and a long-time friend of Suu Kyi’s, as he toured polling stations on Sunday with other EU delegates. How will a woman famous for unyielding moral stands — in 1998 she sat in a car for six days on a country road after police stopped her visiting party members — fare in the political arena of negotiation and compromise? The next step in Suu Kyi’s extraordinary life could reveal what Horsey calls the “essential tension” between her principled and pragmatic sides. “There has to be give and take in politics,” he says. “It remains to be seen whether she will be able to make that transition.” Cooper, who attended Oxford University with Suu Kyi, disagrees. “She’s always been pragmatic, but she’s not had an opportunity to engage,” he says. “And principles are quite a good thing. It’s good that there is somebody who is not prepared to accept second-rate standards.” Even the NLD’s parliamentary toe-hold – it occupies only a tiny fraction of the 440-seat lower house – could compel the party to redefine itself after two decades spent opposing military rule. Suu Kyi’s party was officially banned after boycotting a fraudulent 2010 election that installed Thein Sein’s quasi-civilian government a year ago.