A.T. Robertson Commentary Mark 13:22

"for there shall arise false Christs and false prophets, and shall show signs and wonders, that they may lead astray, if possible, the elect." — Mark 13:22 (ASV)

That they may lead astray (προς το αποπλαναιν). With a view to leading off (προς and the infinitive). Matthew 24:24 has ωστε αποπλασθα, so as to lead off.