VIENNA, March 22 (Reuters) - Salzburg, the home of

Mozart and "The Sound of Music", is not a place known for

radical change.

The picturesque Austrian city, which draws tourists from

around the world to its baroque palaces, Christmas market and

summer festival of classical music and theatre, has had mayors

from only two centrist parties since World War Two.

But now residents' growing exasperation at some of the

highest housing costs in Austria could push them to elect a

young Communist as mayor in a run-off election on Sunday.

"Our key issue, affordable housing, is not just an issue for

people who have to live on a very low income but rather it has

become an issue for the broad majority of people who live off

their work and not their wealth," the Communist candidate,

Kay-Michael Dankl, said in an interview at his party's offices.

If he wins Sunday's run-off against Social Democratic Deputy

Mayor Bernhard Auinger, Salzburg will follow Austria's second

city Graz in having a Communist mayor. The cities are rare

successes for a party not even in national parliament.

"Many people who have lived in the city are moving back to

the countryside or going back (elsewhere) because rents are

extremely expensive," said 26-year-old social worker Michelle.

That Dankl's party, the Austrian Communist Party Plus (KPO

Plus), came a close second in this month's city council election

shows that protest votes need not be the preserve of the

far-right Freedom Party (FPO), which leads in national polls but

came fifth in Salzburg.

"Really this is an election based on personality," said

political analyst Kathrin Stainer-Haemmerle of Carintha

University of Applied Sciences.

Dankl, a 35-year-old historian and former leader of the

Young Greens, grew his party's share of the vote to 23.1% this

month from 3.7% in 2019.

Part of his success has been his personal appeal - he is a

slick, calm speaker with bookish charm and an easy smile.

"He really is a very good and formidable communicator,"

political analyst Thomas Hofer said. "With his personality, his

engaging nature, he is able to soften the harsh edges of the K

in the party name."

He has also won over part of the public by keeping only

2,300 euros ($2,500) a month of his salary and donating the rest

for one-off financial aid to constituents in need. Dankl hopes

his dedication in addressing voters' concerns will outweigh

rivals' calls not to vote for a Communist.

"I think most people in the city of Salzburg now know what

we stand for," he said.

Rattling off figures and examples, he said that on average

renters in his city spend half their household income on rent

and associated costs like heating.

UNREALISTIC

Salzburg's housing crunch is particularly down to a relative

shortage of social housing, according to a report two years ago

by economic think tank Wifo.

Dankl wants to build 1,000 units of subsidised housing a

year for 10 years, a goal his rival Auinger says is "completely

unrealistic". He has pledged 1,500 units over five years.

But the plan resonates even with the wealthy.

"It's just impossible for young people to find an apartment.

There just aren't any subsidised apartments and there should be

a much greater supply," said Brigitte, 71, who rents out two

apartments she owns.

Tourist accommodation is also a factor. Dankl wants to

restrict the use of AirBnB ( ABNB ) to a few weeks a year per apartment.

Auinger, 50, says that will do little to fix the problem.

Both candidates support investigating how many apartments

lie empty for much of the year and say a levy on empty

apartments must be better enforced.

The suspicion is that many of these empty apartments belong

to wealthy absentees, particularly from nearby Germany, who

mainly visit during the summer festival.

"We live right over there in the old town and you can simply

see how during the festival everywhere in the city the lights

are on in the windows, and in winter it's dead," said Christian,

26, who is studying to become a teacher.

Just 821 votes separated Dankl and Auinger in the first

round of voting and the two say they will work together whoever

wins on Sunday.

($1 = 0.9209 euros)