Yes. Free will notwithstanding, it is possible for God to give such a superabundance of grace to an individual as to make it practically impossible for him not to die in a state of grace. However, in its
Decree on Justification, chapter 12, the Council of Trent cautions against anyone presuming to be among such persons:
No one, moreover, so long as he is in this mortal life, ought so far to presume as regards the secret mystery of divine predestination, as to determine for certain that he is assuredly in the number of the predestinate; as if it were true, that he that is justified, either cannot sin any more, or, if he do sin, that he ought to promise himself an assured repentance; for except by special revelation, it cannot be known whom God hath chosen unto Himself. (
source)
That some people are practically assured heaven should not be a cause of concern since God gives everyone sufficient grace to be saved.