Dino prefers pastels.Even before he announced his candidacy for the Senate last week, Democrats were rifling through Dino Rossi’s dirty laundry, looking for any skidmarks that might embarrass the Republican.Rossi has a few pit stains in his past. But not all dirt is created equal.Here then, a rating of Dino’s dirty laundry based on what it would take to make it clean.Scuzzy Threads: Melvin Heide — a real estate mogul, Dino’s first boss and the so-called former Donald Trump of Seattle — swindled investors and spent time in the clink for fraud. Considering they worked together for a decade, and Dino followed Heide to another firm even after the FBI had begun its investigation, it’s hard to buy his story that he didn’t know his mentor was bilking clients. Care Instructions: If the duds were new we’d say dry clean only. But since these clothes date back to the ’80s, you can probably just throw them out.HorsesAssMichael Mastro helped Dino get his start in real estate. He’s also been called our city’s Bernie Madoff.Scuzzy Threads: Didn’t disclose a $50,000 loan from Michael Mastro while working in the State Senate.Care Instructions: Let this one fester in the bottom of the hamper for a bit. If Mastro — alleged architect of a $100 million Ponzi scheme — makes news again between now and November, vigorously scrub with Ajax and steel wool until your knuckles are bloody.Scuzzy Threads: Dino makes money on the speakers’ circuit advising investors to buy up foreclosed property.Care Instructions: This depends on your opinion of real estate speculators. If you think Dino is scum for making bank off of other people’s misfortune, you probably want to tackle this stain with one of those little Clorox sticks. If your attitude on foreclosed homes is “someone’s gotta buy them,” then rock that smudge of Heinz 51 on your collar like it’s your job.Scuzzy Threads: Dino’s firm owes $20,000 in back taxes to the government.Care Instructions: A dab of club soda ought to take care of that.Scuzzy Threads: All of this dirty laundry stacked in one large pile.Care Instructions: Too smelly to ignore on election day.