DY: There are certain positions that if a candidate supports that would disqualify him from people voting for him regardless how good he is on all other issues. For example, if a candidate supported legalizing murder (of living people) even if supported fully funding Yeshivos and supported every other cause important to the Jewish community, it would be wrong for anyone to support him. Especially if in his elected position he could have any influence on effecting that terrible position he advocates into public policy.
Legalizing murder is an extreme example. But who is to say that support of abortion or public support of toeiva aren’t disqualifiers as well.