Don't be so sure.
When Robert Toricelli (NJ senator) got caught taking bribes from a North Korean connected "businessman," it was too late for him to withdraw from his tight race against Doug Forrester.
But that was no problem for the Democrats. They just went to the New Jersey Supreme Court, which ruled (unanimously) that they could "legally replace" Toricelli's name with that of Frank Lautenberg on the 2002 ballot.
Lautenberg went on to win against Republican Forrester.
Kansas is not New Jersey