For most sites, Chrome should do this by default and the default keyword is just the site's URL. So simply:

    rapgenius.com<tab>search terms

autocomplete is supported so you can also just do

    ra<tab>search terms

if rapgenius.com is your first autocomplete result for "ra"

This feels like a bit of a regression. I used to be able to just use the automatic search, but it seems to be breaking for more and more sites recently. Even sites it used to pick up automatically, like tpb, now need to be manually specified.

And there's still no damned excuse for them not being able to search maps.google.com from the omnibox.

aren't we overthinking this a little much?