The polls were wrong in the US. They were wrong with Brexit and they were wrong in Australia. They will probably be dead wrong in Israel too.
It will be the swinging voter who determines the results of the elections, both those who do not want to waste their vote on parties not reaching the electoral threshold, and those who will come out of their boxes to vote which they did not do last time. More than a few Arab voters who have a good life in Israel did vote for Likud last time; this sector is voting right as their lifestyle improves, as opposed to the Arab leadership threatening their economic security.  We can expect more of these citizens to vote right this time.
Liberman will probably lose mandates due to many factors. He is seen as untrustworthy as he swings from side to side, signing an overflow vote agreement with left of center Blue and White. He also is betting on an ageing population of Russian olim who are passing away and whose children are now sabras with a different agenda. Interference in tradition does not gain votes, and that is where Liberman and his ilk will go down. 
The demographics of Israel change every month.  More and more new people are reaching voting age.  More of them come from backgrounds that will vote for the right parties simply because the birth-rate from the religious sector is higher than that of secular families who traditionally voted for the left is waning.
Promises. Promises.  This is a large part of what Blue & White are basing their campaign on.   Even though we do believe in miracles there is no room in the economy in the immediate future to realistically fund promises such as substantially raising wages and pensions. The electorate is not stupid, knows that now is not the time although everyone would love to have wages and pensions rise by a huge percentage.
Blue & White have the utmost confidence in pitting who they believe to be the large secular population against what they perceive to be the religious sector. Most people want to get along in this country; they do not want hatred. The left may have held sway in running the country until now but that is slowly coming to an end. 

The Supreme Court in its recent decision to ban separate seating at a concert in Afula set many teeth on edge. Will their next logical step be to enter synagogues and mosques to demand the separation of men and women?

Like it or not, Blue & White have failed to understand that Israel is a Jewish state with a Jewish lifestyle, not a copy of western countries. There are better ways of bringing the hareidim to participate in the economy and the security of the state which is slowly happening anyway. Thinking outside the box is the preferred trajectory.  We can plan for a two-day weekend. We can replace large parts of the compulsory draft with technology. Using a sledgehammer and financial force is counterproductive.

Then there is the fear factor. Blue and White can try to talk about religious coercion until the cows come home pounding their military chests as they talk what they would do in Gaza.  The truth is that one single attack by a terrorist will turn thousands more to vote right. 

Women’s votes are a subject that the media has not touched upon.  Will women vote for the party led by Ayelet Shaked? We no longer live in a society where a woman would check who her husband or father is voting for and vote accordingly.  Some movement from other parties, both left and right will be a result of women flexing their muscles in their voting choices even though the statistics may not show this.  

And lastly the issue of the difficulties of young and older couples unable to purchase their first home. The only party that has the courage to exponentially increase new buildings is Yamina which will not be pushed around by overseas powers. Once tens of thousands of new units are under construction the law of supply and demand will lower the prices.

It is not impossible for the right bloc to win 61 seats, and maybe more. The polls are not always right and do not determine election results.