Those surveys CAN be misleading and total BS depending on how/where they were conducted as often they contain a sample bias. Example: in 1936 researchers predicted that Alf Landon would defeat FDR based on voting polls. Roosevelt won by a landslide though. Reason: it was a telephone survey and at the time only the very wealthy had telephones so the lower class people (who were more likely to vote for FDR) were not represented in the poll.
Of course this is a very old example and I am sure that researchers take much more care to avoid sample bias today, but there is still that possiblity. Even with an unbiased sample there is usually a 3% variance in accuracy of any poll. All that said, it's probably a lot closer race than that poll indicates. Plus, majority vote doesn't elect a president so I guess we'll all have to see what happens in November. All I know is it will probably be as close as the last election.