To give some context, this is the progressive era, which was a reaction to the excesses of the gilded age. Specifically: trustbusting was big under Teddy Roosevelt, attempting to introduce legislation to break up monopolies, and reform of the political system to make elections much more democratic (e.g. introducing direct elections).

So: this comic sits in the context of this political swing towards more open and transparent government and business, but before it was fully realised. Specifically, the date in 1909 is before the 17th amendment in 1912, which introduced direct election of senators, so the perception was of corrupt, unaccountable senate members.

Probably oil and railroad monopolies and lax regulation of Ford motor company. Also creation of federal reserve in 1913 plenty of special interests vying for control of the money spigot