Futurama is all the work of Matt Groening, may he produce more of it - I am merely a fan making this for fun.
It took everyone a few moments to process it all. The presidential-elect, Chris Travers, the hope of a future come to the present, was gone. And Bender - the infamous robot guerrilla in that time, had just laid out for everyone the unexpected element of the equation: Travers had negated his own existence.
Leela paled at the thought. It wasn't just the ominous warnings Travers had given them. For once, a decent, sensible, honest politician who actually cared about serving the people had come, and gone.
"Hold on!" Leela blinked her one eye in astonishment as Fry came forward and planted himself in front of Bender. "If what you said was, true, then Travers shouldn't have been able to travel to the past at all. I mean," he amended in the hopes of correctness, "now. Which was his past. You know."
"Point is," the delivery boy recovered his usually jumbled train of thought and began to actually make it move out the station. "All those things wouldn't happen yet anyway. But Travers got there... here ... just fine. Therefore, changing the future would not wipe him from existence."
Seconds later, a bemused Travers popped onto the TV screen behind Bender and Fry.
"Yeah," Bender groused back, searching for a counterpoint, but having difficulty. "Well..." Finally, he settled for robotic Bending instinct. "Yo mamma wiped you!"
Travers, having collected himself to speak again to his Earth-wide audience, vanished again.
"Why you-" Fry snapped angrily, and the two were off in a sea of shouting, insults, theories and gesticulations.
Leela, Hermes, Amy and Professor Farnsworth simply glanced at each other for a long moment, communicating more with their expressions than words could. Zoidberg had been shoved out of sight and was too discouraged to approach.
"Ok, Fry has trouble with long division, and he's arguing time-space with Bender?" Leela finally asked, incredulously. "Indeed!" The Professor groused emphatically. "Ten years of college just to get your basic doctorate, then the next ten for the physics special-torate, and twenty for the temporal mechanics super special-torate! There's no getting around the education requirement!"
Suddenly, the old man frowned, and looked down slightly and in the direction of his ancestral uncle, paused in thought. "Unless of course," Farnsworth qualified, "you've seen every time travel episode of Star Trek like Fry probably has. It's about the same thing."
"I think the bigger question is, why that?!" Hermes drastically pondered, pointing to the screen. A by now utterly baffled Travers was flickering in an out of existence as Fry and Bender traded point and counterpoint.
"Hermes," Professor Farnsworth stated, with all the certainly of academic and vast knowledge, "that is a classic case of Schrodinger's Argument! Until Fry and Bender resolve their debate, Travers is trapped in between the states of 'erased' and 'not erased'."
"...So how about this?" Bender finally offered. "The baby meatbag will be around no matter what happens? So Travers, by warning us, prevents all the bad stuff from happening. But since that's what Adult Travers came back here for, he's still gone. But the future is changed." The bending robot looked rather downcast at the thought. "I'm gonna miss leading that robot uprising though."
"Don't worry Bender." Fry put a consoling arm around his robot friend and began to walk off with him. "I'm sure there'll always be another chance some day."
Behind on the TV, as the others noted, Travers began to blur, and then faded out entirely. "Aww, thanks Fry. I promise when that day comes, you'll be spared buddy." Bender said, in all sincerity. "Anyway, it's not like we could break the one universal constant."
"What constant is that?" Leela asked, totally confused.
The laughing from the televised victory podium drew her gaze back. Richard Nixon's head rested atop it now, flanked by Headless Spiro Agnew. "NIXON ALWAYS WINS! AROOOOOOOO!"