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LONDON (Reuters) - Britons began voting on Thursday in local and regional elections expected to give a taste of how far Conservative Prime Minister Theresa May’s dominance extends before next month’s national election.

Thousands of local-level government seats will be up for grabs throughout Scotland and across parts of England and Wales, as well as a handful of newly created regional posts. The results are expected to start coming in from early on Friday.

The outcome should shed some light on how the country will vote in a June 8 national election, and will be pored over for any confirmation of opinion polls that give May’s Conservatives a runaway lead over the center-left Labour Party and the anti-EU UK Independence Party.

Last month May took the surprise decision to call a national election three years ahead of schedule, looking to cash in on her opponents’ weakness and increase her political power at home and abroad ahead of exit negotiations with the European Union.

However, the results of Thursday’s votes will not be a direct proxy for next month’s election. Local elections are held on a different cycle from national votes, and typically see the incumbent party lose ground to opponents.

One of the most closely watched indicators will be in central England, where May has lent her backing to a high profile campaign to win the mayoralty of a large region encompassing Birmingham, Britain’s second largest city.

Traditionally an area dominated by Labour owing to its industrial roots, a Conservative victory would show the effectiveness of May’s attempts to recast her center-right party as the champion of Britain’s aspirational and working classes.

In Scotland, election results look likely to catch up with a big swing in the political mood there since 2012 reflecting the strength of the pro-independence Scottish National Party, particularly in Glasgow.

May will also be watching Scotland to see how far her party’s revival extends in an area where it had suffered years in the political wilderness. Polls show the Conservatives could win more seats in Scotland in the national election than it has held for decades.