Aung San Suu Kyi's party says the pro-democracy campaigner has won a seat in historic by-elections in the country. But could allegations of intimidation undermine the regime's push for legitimacy?

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Nobel Prize winner Aung San Suu Kyi's National League for Democracy party announced to loud cheers at its headquarters that she had won the by-election in Kawhmu, south west of the commercial capital Yangon, raising the prospect of her first role in government after a two-decade struggle against dictatorship.

In total, the opposition says it has secured 19 our of 45 seats in the country's historical poll. And although the results are yet to be officially announced, election observers say there have been no major incidents.

The by-election won't change the balance of power in the country's new-build capital of Naypyidaw, the lower parliament has 650-odd seats, writes Channel 4 News Asia Correspondent John Sparks.

But it is still a big deal because if it is seen to be free and fair - or free and fair enough - then the US, EU and Canada will almost certainly begin to dismantle the sanctions regime that for years has worked to retard the country's economic and institutional growth.

All this poses a dilemma for the governing USDP. Instinctively, they want to retain power. But they also want the investment that a reduction of sanctions would bring. So just how free and fair should they make the by-election?

Obstructing and copying

Clearly, the USDP has been rattled by the euphoric reception Aung San Suu Kyi and her fellow NLD candidates have received. Local government officials have tried to make things difficult for her - for example, they made Ms Suu Kyi address supporters in fields located miles outside major cities, instead of giving her permission to speak in more central locations.

Aung San Suu Kyi had to wait for the tide to change while sitting out in the blazing sun.

Her latest illness was caused in part by the refusal to let her use a speedboat when visiting the Myeik Islands in the south of the country. When the slow boat she was forced to use got stuck on a sandbank, she had to wait for the tide to change while sitting out in the blazing sun.

It is not just about obstructing her, though. The USDP has also tried to copy her. When we interviewed the general secretary of the USDP three weeks ago, Htay Oo told me his party would not be doing any public campaigning or rallies because they didn't need too.

Well, imagine my surprise today when we saw a 10-truck convoy of USDP supporters in central Rangoon, complete with under-age knife juggler to entertain the crowds.

Read more: Is Burma on the brink of a new dawn?

Electoral fraud claims

That's not going to be enough to stop the NLD - who, incidentally, expect to win two-thirds of seats up for grabs tomorrow. So it might not surprise you to hear that there are plenty of allegations of vote rigging and electoral fraud and violence as well.

Today we met a woman who told us a long and detailed story about how a local USDP chairman tried to intimidate her into voting for his candidate. Than Than Htay told me that this official had threatened to get her son sacked from his government job - or transferred to the north - if she did not get her son to stop going to NLD meetings. It sent out a pretty clear message and Ms Htay looked terrified.

Is that free and fair? Definitely not. But will the elections be free and fair enough? I doubt the European Union will judge the contest by western standards - but if these allegations are proven true, the USDP needs to know there will be consequences.

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