The phrase "political ladder" refers to the progression one makes in their political career, moving from lower positions to higher ones, like steps on a ladder. Full definition
As he struggles to keep both young women safe and unearth the answers he seeks, hunted by everyone from the Russian mafia to the Ukrainian police to his own NSA, Jack learns just how far up the American and Russian political ladders corruption and treachery has reached. (bookbrowse.com)
And how are they going to do up the political ladder with this much shallow focus. (religion.blogs.cnn.com)