"ほとんどの政治家は少数派の評判を汚します。"

Simplified Meaning:

When people think about politicians, they often form negative opinions because many politicians make poor decisions or act dishonestly. These bad actions create a negative image of politicians in general, even though there are some who are honest and work hard for the public good. Imagine a school where a few students keep causing trouble, so teachers might think all students in the class are problematic, even though there are hardworking and well-behaved students too. Because of the actions of the troublemakers, everyone in the class has a harder time getting respect. Similarly, good politicians have to work extra hard to prove themselves because the bad ones have already damaged the public’s trust. This teaches us the importance of judging individuals based on their own actions rather than the group they belong to. It also reminds honest politicians and people in other professions to stay true to their values, no matter how others might act.