General Election polling becomes more meaningful after the Conventions at the end of summer. Until then the narrative is how weak a candidate Hillary is (Bernie will not be the Dem nominee and his continued fight will only weaken Hillary); and how enticing it is to complain about things you do not know - like jobs, income inequality and immigration - which attracts Republican voters.
It is worthwhile remembering that the States' Electoral College votes determine the Presidency 270 to win and turnout is critical. So watch the ground game "unexpected" fall events. We know a lot about Hillary. You wonder what will the Clinton machinery highlight about the Donald that we don't know.