Mudslinging goes wrong when it is used indiscriminately and becomes noise that few listen to and most condemn. (Mudslinging)

This year hasn't seen that level of mudslinging, but the tone of the race is undeniably more negative than in the states that came earlier on the calendar. (CBS News)

Enough political mudslinging can lead to a candidate dropping out of the race, especially if his or her family is being viciously attacked. Political mudslinging can become so ugly that is can cause a potential nominee to lose favor with his or her political party. (WiseGEEK)