The phrase "already made a mark" is correct and usable in written English.
It can be used to indicate that someone or something has had a significant impact or influence in a particular area or context.
Example: "The young artist has already made a mark in the contemporary art scene with her innovative techniques."
Alternatives: "has already left an impression" or "has already made an impact."
He has already made a mark with the public.
Imitrex has already made a mark by pointing out that it does not cause drowsiness, something feared by migraine sufferers.
At 36, she has already made a mark in several fields: economic theory; applied economics, from auctions and industrial organisation to macroeconomics; and econometrics.
Le Stanze del Vetro, which opened its new galleries on the island of San Giorgio Maggiore last September, has already made a mark.
But she worried that it would be too little, too late — especially since others have already made a mark through political Facebook ads that were not properly labeled.
Twitter has already made a mark in the literary world, through experiments like Jennifer Egan's tweet-by-tweet New Yorker story, "Black Box," and Ben Okri's line-a-day poem — not to mention the continuing debate over whether that microblogging service has turned the once-contentious literary world into a boring mutual appreciation society.
It all sounds very arcane and anorakish, but the regulations have been changed this season, and it is already making a mark.
Mr. Daellenbach, the last remaining original member of the group, is preparing the way for its future, recruiting young performers who are already making a mark.
The Internet of Things doesn't have to mean letting Silicon Valley in through your remotely unlocked door: British companies, from established players to startups, are already making a mark.
FC Cincinnati, which currently plays in the United Soccer League, is breaking records for attendance and already making a mark in MLS.
