Paul, who turns 37 on Friday, racked up 28 points, six rebounds and eight assists to inspire the Suns to a 129-109 win in the Western Conference best-of-seven playoff series.
It looked likely to be a tight game going into the fourth quarter as the Suns were only up by six, 89-83, but Phoenix turned it into a comfortable win after scoring 40 points in the final period, including 14 from Paul.
"You guys tell me, you're watching the same thing," fellow Suns guard Devin Booker -- who had a team-high 30 points -- told reporters when asked about Paul's longevity.
"It impresses us every time we see it, but it doesn't surprise us. It's just the will to win."
The Suns head to Dallas with a 2-0 lead and will hope Paul can keep coming up clutch. The 36-year-old, however, is keeping his feet on the ground.
"You've just got to lean on the work," Paul told reporters, explaining his ability to keep playing at the highest level. "It all goes back to the work.
"You can't cheat the game. You've got to do the strength and conditioning, you've got to lift, you've got to get your rest, you got to get your shots up.
"When you do that, you live with the results."
Dallas star Luka Doncic did his best to keep his team in it with a standout 35 points, five rebounds and seven assists on 13-of-22 shooting, but little else came from a tame Mavs side, leading coach Jason Kidd to ask the rest of his squad for more.
"He had a great game, but no one else showed. We've got to get other guys shooting the ball better," Kidd said postgame. "We can't win with just him out there scoring 30 a night -- not at this time of the year. And we're playing the best team in the league, so we've got to get other guys going."
Game 3 is on Friday in Dallas.
Heat take 2-0 lead over Sixers
Meanwhile, in the Eastern Conference, the Miami Heat stretched their playoff lead to 2-0 after beating the Philadelphia 76ers 119-103 on Wednesday.
Bam Adebayo and Jimmy Butler scored 23 and 22 points respectively for the hosts who had too much for their opponents.
Philadelphia will be desperately hoping MVP candidate Joel Embiid can return from suffering a facial fracture and concussion he suffered against the Toronto Raptors to help get its postseason hopes back on track.
However, after Wednesday's defeat, Sivers coach Doc Rivers said he was still unsure whether Embiid will be fit enough for Game 3.
"He's got so many steps to go through, and I don't think he's cleared any of them right now. So we just have to wait and see," he told reporters.
Philadelphia hosts Game 3 on Friday.