It makes sense. Currently, there is a massive imbalance (3 or 4 to 1 the last poll I saw) in favor of Democrats in the younger demographics, largely because the Republican party often champions causes that younger persons consider outmoded, setting up a generational disparity. This seems like an unusually well-done (despite the age of the work in question, this will only be the first or second presidential election for the age group that the movie was originally successful, so it's an extremely apt choice) effort to reach across that gap.
Have to disagree there. I see it as a terribly transparent attempt to look "hip", despite the fact that Pokemon isn't nearly as popular as it used to be and the movie in question is 11 years old, wasn't all that great, and the series suffered from a bad case of sequelitis. It's like a congressman quoting one of the Land Before Time movies.
In any case, the newer generations tend to be more accepting of ideas that are historically anti-Republican (gay rights, abortion, Equal Rights Amendment, etc). It'll take a lot more than this to sway younger voters.