What to watch for in Germany's state elections

By Sarah Marsh

BERLIN (Reuters) -Here is a rundown of the most important aspects of the two state elections taking place in eastern Germany on Sunday in which the far-right AfD party is polling strongly and the far-left is expected to come third:

WHO IS VOTING AND WHAT ARE THEY VOTING FOR?

Thuringia and Saxony vote on Sept. 1 and Brandenburg follows on Sept. 22. Together the three states have around 8.5 million inhabitants - similar to the population of Switzerland - and account for 10% of Germany's population.

Voting patterns in the formerly Communist-run east remain very different to those in the west, more than 30 years after German reunification, but the elections provide a snapshot of citizens' mood. Immigration, the economy and relations with Russia are the main focus of both the far-right and far-left.

Germany's state governments and parliaments oversee the police, courts, education and culture and determine the composition of the Bundesrat (federal upper house of parliament), which has a say over some national legislation.

WHO IS LIKELY TO WIN?

While a centre-left coalition governs in Berlin, three opposition parties dominate the east German political landscape. They are the conservatives and two anti-establishment parties: the far-right Alternative for Germany (AfD) and the Sahra Wagenknecht Alliance (BSW), which is conservative on social policy and far-left on economics.

Both the AfD and the BSW are eurosceptic, anti-immigration, Russia-friendly and against military support for Ukraine.

Polls suggest the AfD could come first in all three states with numbers in the range of around 24-32% of support, which would mark the first time a far-right party has been largest in a German state parliament since World War Two.

The conservatives are vying with the AfD for first place in Saxony, while firmly in second place in Thuringia and running neck-and-neck for second place with Chancellor Olaf Scholz's centre-left Social Democrats (SPD) in Brandenburg.

All three parties in Scholz's coalition are forecast to perform poorly, with both Greens and the pro-business Free Democrats (FDP) appearing set to fall out of the Thuringia state parliament for failing to reach the 5% threshold.

The SPD is on track to win just 6-7% of the vote in Saxony and Thuringia, a poor performance for what has long been one of Germany's two big-tent parties.

Meanwhile, the BSW is typically ranging between 11-20% of the vote. It is set to near obliterate the far-left Left party, from which it splintered, in Brandenburg and Saxony, while swiping more than half its support in Thuringia.

At national level, the AfD and BSW are polling respectively at 16-19% and 7-9% support but in these three eastern states, they look set to take nearly half the vote collectively.

WHO WILL GOVERN?

Given the AfD is unlikely to reach a majority of votes alone, it would need to get the support of another party to form a coalition or a minority government in the three states. But so far, all other parties have refused to work with the party.

The AfD would likely portray manoeuvres to keep it out of power as undemocratic, political analysts say.

Meanwhile a conservative party ban on forming a coalition with the far-left Left party further complicates coalition mathematics in particular in Thuringia, where the latter has some 13% of the vote.

As such the conservatives could seek to form a coalition or minority government in Thuringia with support from the BSW.

In Saxony and Brandenburg, the current coalitions of conservatives, SPD and Greens could scrape enough support to continue in power - but if not, the established parties may also need to also rely on the BSW.

WHAT WILL THAT MEAN FOR GOVERNMENT?

If the AfD achieves one third of the parliamentary seats - which it could do in Saxony and Thuringia - it would have a blocking minority for certain decisions, such as changes to the state constitution and judge appointments.

Moreover, as first-placed party, it would traditionally nominate the president of the state parliament, although this requires a vote and it would likely not receive enough support.

The strength of the AfD and BSW could result in awkward coalitions or minority governments that struggle to push through legislation.

(Reporting by Sarah Marsh; editing by Philippa Fletcher)