But while O'Dwyer, who finished second in this tournament in 2011, and Chouity, best known for winning the 2010 EPT Grand Final, have the most chips, they're certainly not the only talent left in this tournament.
Also gunning for this year's EPT London title and the £700,000 first-place prize are players like Theo Jørgensen, Chris Moorman and Ruben Visser.
This event is particularly significant for Jørgensen since he has a shot at completing poker's Triple Crown, having already won a WPT title and a WSOP bracelet.
Chris Moorman, who is also looking for his first EPT title, is staying realistic when it comes to his expectations for tomorrow.
"I just play one hand at a time, try to play my best and see what happens," Moorman told PokerListings.com after the chips were bagged.
"And if it doesn't happen, then I guess it wasn't meant to be. As long as I don't make any terrible mistake, I won't be too annoyed."
Here are the final 16 players' chip counts heading into Day 5:
Steve O'Dwyer (United States) - 2,279,000 Nicolas Chouity (Lebanon) - 2,124,000 Tamer Kamel (United Kingdom) - 2,115,000 Pasi Sormunen (Finland) - 1,834,000 Niall Farrell (United Kingdom) - 1,581,000 Theo Jorgensen (Denmark) - 1,474,000 Mikhail Korotkikh (Russia) - 1,372,000 David Colin (France) - 1,088,000 Chris Moorman (United Kingdom) - 1,061,000 Mantas Visockis (Lithuania) - 915,000 Ruben Visser (Netherlands) - 827,000 Christopher Frank (Germany) - 821,000 Daniel Erlandsson (Swedish) - 700,000 Bassel Moussa (Lebanon) - 685,000 Olof Haglund (Swedish) - 453,000Mercier, Obrestad Among Day 4 Casualties
Everyone who returned to the felt today was guaranteed to make money but when the day was done half of the field had been forced to leave short of the truly big prizes.
Headlining that group were Team PokerStars Pro Jason Mercier and former WSOP Europe main event champion Annette Obrestad.
Mercier bowed out in 25th place after losing a preflop all-in race with A-9 against pocket sevens.
Obrestad, meanwhile, busted thanks to a lost flip against Nicolas Chouity. The young Norwegian pro finished 23rd.
Also busted today were WSOP bracelet winner Max Greenwood (17th), youngest-ever EPT champ Mike “Timex” McDonald (20th) and online crusher Russell “rdcrsn” Carson (26th).
The EPT London main event will reach a winner Saturday. Check the PokerListings.com EPT News section for the update.
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