In purely numerical terms, Israeli Arabs make up enough of the electorate — about 17 percent, equivalent to slightly more than 20 seats in the 120-seat Knesset — that if they turn out en masse this year, their vote could push Gantz’s presumed bloc over the top on April 9. On the other hand, if they sit out the election in larger than usual numbers, it’s likely to be the right-wing bloc led by Netanyahu that will benefit.