I wonder about the young liberals who demonstrated against Erdogan. Despite being Kurd, Demirtas must have some potential among this population right?
It's possible. Demirtas got 9.1% in Istanbul, almost doubling the HDP result in the local election held in March (4.8%). If you compare the district results, Demirtas improved remarkably in some 'westernised' areas like Besiktas (HDP 1.7%/ Dem 6.7%), Kadiköy (1.8% to 6%) or Sisli (4.1% to 9.9%). In Beyoglu, where is located the Gezi Park, Demirtas got 13.1% (HDP 7.3% in the local election). Demirtas did better in Esenyurt on the European side (17.2%) and Sultanbeyli on the Asian side (16.2%), both working class. Sultanbeyli was the district where Erdogan did better (69.6%) and the only one where Ihsanoglu came third (14.2%). It's a fast growing suburb (82k in 1990, 298k in 2011) settled by migrants from Bulgaria since 1945, according to Wikipedia. The Turkish version says nothing on the proportion of Kurdish population there, although it gives some interesting historical details.
Notably hilarious result in Sultanbeyli where Ihsanoglu actually came third, hahaha.
To be fair, CHP and MHP did even worse in the local elections coming 5th and 6th behind Felicity Party and HDP. Great map, btw.