Absolutely. The sentence should be:
The Congress is acting as the
Using "likewise" in this sentence is a mistake.
Informally you might hear "The congress is acting like the president
did." Perhaps this informal use of "like" caused a confusion with "likewise."
The Collins COBUILD English Dictionary (HarperCollins, 1995) lists "likewise" as
an adverb, and defines it like this:
You use "likewise" when you are comparing two methods, states
or situations and saying that they are similar: All attempts by Socialists
to woo him back have been spurned. Similar overtures from the right have
likewise been rejected
So, "likewise" does not fit into the sentence you submitted. You need a conjunction such as "as."