Will Obama give her a blanket pardon? I'm not sure. Especially if there are no charges yet filed.
Gerald Ford pardoned Nixon *before* he was indicted over the Watergate scandal.
Reading the pardon, I can see it as a template for Hillary: it'll take too long for a trial to start, harms the "tranquility of the nation", "for all offenses
The best part about a preemptive pardon (before indictment) is that it stops the whole process cold. No need to further pursue an investigation if there will definitely be no charges filed? Stops the FBI investigation and saves the embarrassment of the spectacle of the DOJ ignoring the FBI report for political reasons. Kills any chance for a possible Republican administration to go after her too.
Hillary can go on proclaiming her innocence and no one can challenge her anymore.
The only problem with that is I (and probably you as well) do not see Obama willing to spend the political capital to do this, even if it is to save the election for his political party.