The migrant vote

"For love," said Juan Diaz with a grin, when asked why he moved to Berlin. He also immediately fell in love with the city, in which so many nationalities live side by side like a demographic patchwork quilt.

Diaz is an American from Miami, with Cuban parents who fled Fidel Castro's regime - "a complex identity," he sums up. For the last seven years, Diaz has also been a German citizen. "I applied for citizenship because I wanted to have a say. I wanted to decide who becomes chancellor and who makes up the parliament."

Nearly 16 million people like Diaz live in Germany, according to 2011 survey by the Federal Statistical Office (Destatis) - people with an immigrant background who either left their former home or whose parents or grandparents came to Germany. Many of them are either too young to vote, or not German citizens. Only those with a German passport are able to cast a vote - an exception being EU citizens, who may vote in local and European elections, though not at the national level.

According to Destatis, around one third of German citizens with an immigrant background will be allowed to vote in September's federal election. And that number is growing: in 2011, more than 100,000 people were granted citizenship in Germany.

Party preference linked to country of origin

But not all of these new citizens will make the trip to their local polling place. A 2012 study from the Federal Office for Migration and Refugees showed that people with immigrant backgrounds cast their ballot fewer times than the average.

In the 2009 parliamentary election, 72.3 percent said they had voted, compared to 81.5 percent in the general population. An exception are those that are part of the workforce: in both groups, the percentage of those who voted was about 80 percent.

Not vote? For Diaz, the idea is unthinkable. "I always find it fantastic when my voting card appears in the mailbox," he said. The right to vote is a valued fundamental right, one the Cuban-American refuses to give up. As a mediator for conflicting parties, Diaz travels quite a bit, often in the Balkans. In those cases when he isn't home to vote, he said, he simply votes ahead of time by post.

Those migrants who do vote often give their support to the Social Democrats (SPD) or the Christian Democrats (CDU), according to election research. Ingrid Tucci, a social scientist at the German Institute for Economic Research in Berlin who has studied party loyalty among immigrants, said the majority tends to vote for one of the two major parties.

Those who came to Germany as guest workers from southern Europe, Yugoslavia, and Turkey in the 1950s and 1960s tend to favor the SPD. These immigrants are usually part of the "traditional working class."

Repatriates, ethnic Germans who have come back to Germany from the former Soviet Union since the end of the Cold War, tend to prefer Chancellor Merkel's CDU and its Bavarian sister party Christian Social Union (CSU).

Migration experience is important

Tucci believes these party loyalties are strongly related to the migration experience. For this reason, the CDU has made migration for repatriates a priority, and given its support to targeted integration policies for this group. By contrast, some politicians in this party have often held a negative attitude towards foreign workers.

Religion, according to Tucci, plays a relatively small role. According to her research, religion, education level and occupational status "have a minimal impact on party preference."

Tucci believes there to be a direct link between voting behavior and the migration experience. She said, however, that more research is needed for this link to be better understood, since the clear preference for either the CDU or SPD tends to wane in second generation immigrants.

Figures from 2011 show that around 18 percent of the second generation, the children of immigrants, would vote for the Green party. Less than 40 percent would support the CDU or the SPD, statistics that aren't too different from the rest of the German population, said Tucci.

Diaz is still undecided ahead of the September election. In the past he has worked for a CDU politician, participated in several meetings of the Green party and often attends political discussions put on by all the parties.

In previous years, he said, Germans attending these discussions often told him that "as a foreigner, [he had] no right to speak." That made ​​him angry. But now he's able to make his voice heard - officially.