JUDY WOODRUFF: Now, the first of two stories from the once secretive and closed nation of Burma, officially known as Myanmar. The country, long under military dictatorship, is about to hold an election, the most visible sign of its political thaw.
Our report comes from special correspondent Kira Kay and producer Jason Maloney.
KIRA KAY: It's a scene many Burmese thought they'd never see: opposition leader and Nobel Peace Prize winner Aung San Suu Kyi on the campaign trail once again.
Today, she's on a 12-hour meet-and-greet marathon to the city of Mawlamyine. Mother Suu, or simply "The Lady," spent 15 of the last 22 years sentenced to house arrest by a military dictatorship that rejected her party's landslide in 1990 elections.
But today, Aung San Suu Kyi is an official candidate for a vacant seat in Burma's parliament. Members of her party, the National League for Democracy, or NLD, are contesting another 47 openings.
AUNG SAN SUU KYI, Burmese pro-democracy leader (through translator): We formed this party genuinely support the cause for democracy, for democracy to take root and to fully protect human rights. These policies, however, have not as yet become successful, honestly speaking.
Our people have not yet fully achieved human rights. In fact, there is still no Democratic system in this country.
KIRA KAY: Indeed, the campaign has not been perfectly free. Local authorities have sometimes refused permits for NLD rallies. And part of a speech Aung San Suu Kyi was permitted to give on state television was censored when she tried to criticize past government abuses.
But even though these vacant seats will represent only 7 percent of parliament, that the NLD can run at all is an extraordinary change of events for Burma. Burma has been ruled by the military for half-a-century. In 1989, they renamed the country Myanmar. Sanctioned in the 1990s for its poor human rights conditions, Burma's isolation increased. It is now one of the poorest countries in the world.
In 2005, the military abruptly moved the capital to a manufactured spread of imposing concrete in the middle of the country. This 16-lane highway through the center anticipates a day when diplomatic motorcades will roll through.
In the grand halls of the massive parliament building, 25 percent of the seats are reserved for the military. The outside world viewed 2010 elections to fill the rest of the seats as a sham. But last year, Burma's curtain started to lift with the inauguration of a new president, Thein Sein. A former general himself, he put aside his uniform to lead as a civilian.
DEREK MITCHELL, U.S. special representative to Burma: Because Burma is changing, our policy is changing. We are now talking in terms of being partners in reform.
KIRA KAY: Ambassador Derek Mitchell became President Obama's special representative for Burma in August. We caught up with him on his sixth visit to the country.
DEREK MITCHELL: Aung San Suu Kyi is out campaigning on an almost daily basis. That was unheard of just really a year ago. You also get a sense that the media and civil society are a little bit -- are freer. Certainly, the media is. Civil society is nascent, but people are now speaking openly.
They had 1,000 or more political prisoners and they've released now hundreds of the most important leadership of the democratic movement. So we see in a whole host of areas, we've seen change.
PHONE WIN, opposition activist: After 20 years, they know that they cannot develop with the current political system, so we have to change.
KIRA KAY: Independent opposition activist Dr. Phone Win says two traumatic events served as a wakeup call for the Burmese government.
First, in 2007, the so-called Saffron Revolution, street protests led by monks over rising fuel prices that ended only with a brutal military crackdown.
PHONE WIN: The military government, they lost their credibility, they lost their legitimacy.
KIRA KAY: It was a turning point for the country?
PHONE WIN: Yes. After the Saffron Revolution, the military government started thinking seriously about how to repair the damage. Another reason is after the 2008 Cyclone Nargis, it's very big loss and a huge damage. They understand that they have to cooperate with the international community. They changed their mind-set.
KIRA KAY: The government's path to reform led to two landmark events in 2011: Aung San Suu Kyi's meeting with President Thein Sein last August, heralding her return to politics, and the December visit of the first American secretary of state in 50 years.
Burmese like Soe Myint are grasping the moment.
SOE MYINT, opposition supporter (through translator): It was a striking scene for us to see an American secretary of state giving warm treatment to a woman just released from arrest. Then came subsequent visits by nearly 10 foreign ministers of other countries within a period of one month. All of this seemed to me to be extraordinary events.
We are way behind the world. We are way behind Asia. So we must go down this path, because this is a final chance for our country.
KIRA KAY: And the NLD is also taking this chance to build their political ranks beyond Aung San Suu Kyi's celebrity status.
Many hours away, in a village in central Burma, a smaller but perhaps just as important campaign is under way. Zayar Thaw is 31, an activist, former political prisoner and now a first-time candidate. Approached by Aung San Suu Kyi to join the NLD, he says it was a tough choice.
ZAYAR THAW, opposition candidate: I'd to be an activist, because it's just more free. I can express myself clearly, but The Lady said the NLD needs a new blood and young blood. So I accept it with my -- with a pleasure.
(through translator): Even though this wicked dictatorship system is disappearing and collapsing as we speak, I'd like to request your support and vote for the NLD, which is trying to uproot this wicked system once and for all from Myanmar's soil.
KIRA KAY: Zayar Thaw is a long shot to win. He's running in a township bordering the national capital, where residents may not be so quick to vote against the sitting government.
But it's clear the NLD is grooming him for the more pivotal 2015 elections, when most of parliament's seats will be at stake. At least one member of Zayar Thaw's constituency has already changed his mind. Retired soldier Maung Pyone says in the 2010 elections, he was too fearful to vote against the military.
MAUNG PYONE, retired soldier (through translator): Now we can vote freely. We can choose our favorite party as we like. In a way, all powers have been transferred to the people, and they can choose a trustworthy leader.
KIRA KAY: But whether this new freedom will be permanent is still an open question. There are worries of divisions between reformers in the government and hard-liners who may fear losing their power and economic benefits.
The military's tailor-made 2008 constitutional entrenches it in power, something that won't change with this election.
At a press conference following her meeting with U.S. Special Envoy Derek Mitchell, Aung San Suu Kyi told me of her concerns.
What will convince you that progress is irreversible?
AUNG SAN SUU KYI: That the military is fully behind the process. If you have read the present constitution, you will understand that, without the backing of the military, we can never say that we are really on the road to democracy.
KIRA KAY: Another problem remains the humanitarian crisis in the ethnic minority Kachin State, where 30,000 people are displaced. And human rights groups allege the Burmese army continues abuses against civilians in their effort to rout separatist rebels.
Special envoy Mitchell says the United States is closely watching developments.
DEREK MITCHELL: There's concern at every level. Certainly, they have a long period of transition, because it is reversible. It is clear that this has only been only six or seven months.
So, until we see changes in the constitution, until we see unconditional releases of political prisoners, all political prisoners released, until we see the election coming up, by election, being free, fair and transparent, we have to be very careful.
KIRA KAY: Following Secretary of State Clinton's visit, the U.S. partially waived its opposition to support for Burma from the World Bank and other international development institutions. But direct economic and political sanctions remain in place.
What might be a benchmark for the lifting of our sanctions?
DEREK MITCHELL: I think we have to take - we'll take that case by case. I think the key factor in sanctions is whether sanctions are getting in the way of reform. Where there any restrictions in our ability to assist the country in reform, we ought to be taking another look at.
KIRA KAY: Opposition activist Phone Win believes sanctions need to go if the country's hardliners are to be won over.
PHONE WIN: Hardliner is everywhere, not only in the government, but also in the public and political groups.
If we can see the development of our country, I think everybody will happy and everybody will go to the same direction. Otherwise, if we sanction and isolate, there will be no economic development and then we start fighting each other, struggling each other, which is not good for our country.
KIRA KAY: Back on the road to Mawlamyine, Aung San Suu Kyi's convoy rolled on into the night. And at the final destination, huge crowds kept calling her back onto the balcony.
The vote on April 1 will be a first step in determining if the changes that have come so quickly to Burma are here to stay.
JUDY WOODRUFF: Aung San Suu Kyi, who is 65, has been off the campaign trail since the weekend, ordered by her doctors to get some rest.
Online, you can see a slide show of images from an opposition rally in Burma.
In her next story, Kira examines civic activism and press freedom and censorship. Her reports are a production of the Bureau for International Reporting.