Donald Trump's claim that immigrants are pouring in to vote against is simply not valid, for a number of different reasons. Immigrants cannot simply 'vote' if they have not been citizens for more than five years, which makes it incredibly hard for any illegal immigrant to come and cast a vote against Trump.
These accusations against illegals pouring in to vote 'against' him are simply nonfactual, and he hopes that with this rhetoric, he can incorporate a 'them vs us' attitude to the American public. He virtually envisions Hispanics as an enemy to the success of America, when in fact, could not be further from the truth.
He rooted this argued of his from the exchange he had with Art Del Cueto, vice president of the National Border Patrol Council. When discussing as to why they allow Hispanics to cross the border, along with assistance doing so, Trump insinuated that the motive of these Hispanics was to 'vote' so they can rid him once and for all; however, that was not what Art Del Cueto stated at all. What Del Cueto may have been saying is that they are checking criminal records of undocumented immigrants to helping to process the citizenship applications of legal immigrants in time to allow them to vote. That is not to say that these immigrants are not completely in solidarity with Trump's notions and policies, but Trumps resistance to having the pouring number of Hispanic immigrants coming to the U.S show that he IS aware of how unfair his immigration policy is regarding the border.
So, are Hispanics pouring into the country just to 'vote'? No, they are coming here for a better life. Obviously they would also wish to speed up the process of citizenship so they can participate in politics and voting. If Trump feels threatened that these immigrants are out to get him, than he has already recognized that his policies are unfair.