The Missouri Democratic Party is preparing to file a Federal Election Commission complaint against Joe the Plumber for "illegally advertising" on behalf of state Sen. Chuck Purgason (R).

Samuel "Joe" Wurzelbacher recently purchased a statewide ad supporting Purgason, who is Rep. Roy Blunt's (Mo.) top rival for the Republican Senate nomination.

The Missouri Democrats plan to file an FEC complaint on Friday against Wurzelbacher on the ground his advertising campaign "committed numerous violations of the Federal Election Campaign Act."

In a release, the party cited, "potential illegal in-kind contributions" and "failure to comply with disclaimer requirements" as two possible violations.

"If Joe The Plumber wants to meddle in Missouri politics, the least he can do is follow the law," party spokesman Ryan Hobart said in a statement.