(ABC News) -- Kid Rock slammed on Friday a left-leaning watchdog group's claim that he has violated federal election law by acting like a Senate candidate, while failing to register his candidacy or comply with campaign contribution rules.

"I am starting to see reports from the misinformed press and the fake news on how I am in violation of breaking campaign law," the Michigan native, whose real name is Robert Ritchie, wrote on his website.

He continued, "#1 I have still not announced my candidacy. #2 See #1 and go f--- yourselves."

The musician, 46, has teased a possible GOP challenge to Sen. Debbie Stabenow, D-Mich.

The watchdog group, Common Cause, filed a complaint Friday with the Federal Election Commission and U.S. Department of Justice.

"Regardless of whether Kid Rock says he’s only exploring candidacy, he’s selling 'Kid Rock for Senate' merchandise and is a candidate under the law. This is campaign finance law 101," said Paul S. Ryan, Common Cause’s vice president for policy and litigation, in a statement Friday.

Ryan continued, "Given the activities we’ve documented in the complaint, he can’t reasonably claim to be merely testing the waters of candidacy and thus exempt from candidate filing requirements. He is a candidate and is obligated to abide by all the rules and make the same disclosures required of everyone else running for federal office."

Common Cause is asking the FEC and DOJ to launch investigations into Kid Rock’s "campaign," and to "impose appropriate sanctions for any and all violations" along with "additional remedies as are necessary and appropriate to ensure compliance" with the Federal Election Campaign Act (FECA).

While Kid Rock is attracting the ire of many on the left, Republicans are encouraging him to run.

"Looking forward to having @KidRock in Congress to help #MAGA," Rep. Sean Duffy, R-Wisc., tweeted Friday night. "The GOP cloak room will never be the same #BornFree."

And last month, the head of a super political action committee aligned with Senate GOP leadership said the super PAC would "actually be very interested in his candidacy.”

"I certainly wouldn’t count him out," Steven Law, president of the Senate Leadership Fund, said on C-SPAN. "If you’re watching, Kid, we hope you run."