Round 17 is over!
Category, Name, # of votes
I, Ts’ai Lun, 6
L, Julius Caesar, 4
P, Karl Marx, 5
S, Louis Pasteur, 7
Marx lost the tie-breaker with Confucius. I’m surprised Lenin is still hanging around - Caesar was largely responsible for the Romanization (such as it was, of course) of Europe with enormous consequences for the future of global history, while Lenin’s influence was, imho, much less so.
But that’s why we play the game, eh? 
Remaining names:
Inventors
James Watt, British Scientist, Invented Steam Engine, Invention and Exploration
Johann Gutenberg, Scientist, Inventor of Printing Press, Invention and Exploration
Thomas Edison, American Scientist, 1,000+ inventions, Invention and Exploration
Leaders
Augustus Caesar, Roman Princep, Founded Roman Empire, Leader
Genghis Khan, Mongol Ruler, Founded Mongol Empire, Leader
George Washington, American Statesman and General, Fought For Independence of United States, Leader
Lenin, Russian Leader, Founded Communism in Russia, Leader
Sui Wen Ti, Chinese Emperor, Reunited China, Leader
Philosophy
Aristotle, Greek Philosopher, Philosophy and Arts
Confucius, Chinese Philosopher, Founder of Confucianism, Philosophy and Arts
Plato, Greek Philosopher, Developed Platonism, Philosophy and Arts
Science
Albert Einstein, Scientist, Physicist, Theory of Relativity, Science
Charles Darwin, British Scientist, Theory of Evolution, Science
Euclid, Greek Mathematician, Science
Isaac Newton, British Scientist, Theory of Universal Gravitation and Motion, Science