Obama received secret service protection earlier than any POTUS candidate ever has, (in May of 2007 I believe), because of the sheer volume of threats against him.

I don’t find it at all implausible that his threat level has quadrupled, compared to Bush. Let’s also remember that the SPLC has reported that recruitment in and activity by white supremacist groups leaped upward last summer, and has only continued to increase since the election.

Also, the USSS has to check out every threat, no matter how flimsy it is. And rightly so.