Seyfi Demirsoy is one of the localities of Altındağ; it had 5,889 registered voters at the 2011 parliamentary election.
The neighborhood parts ways with the district as a whole. At the 2011 parliamentary election it went to CHP with 51.8%, while across Altındağ the leading party was AK Parti, with CHP here running 29.3 points above its district average. At the 2010 referendum 69.5% of the neighborhood voted 'no' — 36.8 points above the district average.
At the 2009 local election the neighborhood went to CHP with 46.0%, while Altındağ as a whole was won by AK Parti. The picture has not changed since 2009: CHP has finished first in all of the last 5 elections.