Iowa Sen. Chuck Grassley's Twitter account, and his cavalier use of abbreviations seemingly of his own creation, are a powerful force in the Twitter Universe. He has, at this time, over 65,000 followers.

He's warred with PETA on it, and called out President Barack Obama several times on the account, sometimes saying things he had to walk back later.

But perhaps no Tweet developed a following more of its own than the Tweet with a single "U" sent out by Grassley Wednesday afternoon: Grassley Perplexes Twitter with a Single Letter. (Mashable)

Iowa Senator Chuck Grassley and Twitter aficionado is known for his oft-mispelled tweets and ability to cram as many thoughts as possible into 140 characters — or none at all.

Grassley left Twitter users with unanswered questions on Wednesday after tweeting what appears to be a typo. It was just the letter "U.

Twitter users took it upon themselves to solve the riddle with song lyrics, puns and other responses you'd expect from trolling.

I collected several Iowa responses in the Storify above, peppering in a few national quips as well. But there are some more clever examples at the Mashable link as well.

What do U think? Have a favorite reply? Tell us in comments.

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