The Israeli election is not exactly a good indicator of charedi population
Satmar for example do not vote in elections and Rav Shmuel Auerbach said there was nobody to vote for and his followers did not vote (Likely costing UTJ a Knesset seat) also not all charedim vote for charedi parties. More than a few voted for mainstream parties like HaBayin Hayehudi and Likud (They know this from election results in Charedi districts especially Bnei Brak
from the 2015 election results in Bnei Brak
United Torah Judaism won 59.35%
Shas 23.97%
Yahad 5.5%
Likud 4.57%
Habayit Hayehudi 2.35%
Zionist Union (Labor) 1.28%
Kulanu 1.15%