He fights for goodness and justice using his amazing ability to travel through time. He could just play the stock market and wallow in money but instead he is the virtuous superhero known throughout the land as:
When we last left Time Traveler Man he was dealing with the sticky problem of a wholly corrupt and entirely unstable President. A citizen was begging for help as the country slid into civil war and chaos...
"Time Traveler Man!"
"I know you said your time travel powers only allow you to travel a short distance in time and so you can't stop this President from being elected, but isn't there some scandal, or some short term way to bring him down?"
"I wish there was, Citizen." Replied Time Travel Man sadly. "Many scandals that you know of have been things I've exposed. The embarrassing Press Conference in Russia was through my careful arrangements. Scandals with payments to Playmates and Porn Stars. Overt lies emphatically exposed. But none of them has budged the Republican support for him."
"Darn!" Cried the citizen. "What would it take? Maybe if he started a nuclear war?"
"117 times now."
"Wow." Responded the citizen quietly. "You've been busy."
"I've been busy."