Forex.com, one of the retail forex brokerages of Gain Capital, announced it is temporarily increasing the margin requirements on the EUR forex pairs in order to protect its clients from potential market volatility around the upcoming general elections in Germany.
Even though the outcome of the elections appears predetermined with a stable lead of the ruling coalition of Angela Merkel, a surprise is never impossible and it could affect the markets and the Euro rate significantly.

Do you think other brokers will hike their margins too?

I believe Forex.com will not be the only one broker to increases margin requirements.
I do not expect any significant movements, but - it is just what I am expecting

There will be no surprise at all. The most boring election battle ever between Mama Merkel and Merkel with beard. Why increase the margin requirements for EUR and DAX?