http://www.vox.com/2016/10/8/13212310/mike-pence-president-trump-drop-out
"It’s not as if Pence didn’t know what he was doing. By the time Trump picked him as his running mate on July 14, Trump had already: Called for a “total and complete shutdown” of Muslim immigration to the United States, Referred to Mexican immigrants as “criminals” and “rapists”, Mocked a New York Times reporter for his disability, Said that an Indiana-born judge of Mexican descent couldn’t do his job and judge a case fairly because of his heritage (Pence is from Indiana), Lied about his opposition to the Iraq War, Praised Vladimir Putin, Retweeted white supremacists, Tweeted an image of Hillary Clinton with a Star of David superimposed over a pile of money, a symbol widely viewed as anti-Semitic, Suggested Sen. Marco Rubio had a small penis, called Carly Fiornia ugly, and implied that Sen. Ted Cruz’s father was involved in the Kennedy assassination despite no evidence, Claimed, falsely, that “thousands” of Muslims in New York and New Jersey had cheered the 9/11 attacks, Barred the Washington Post from his rallies and threatened to sue because he didn’t like its reporting, Suggested he would pay the legal fees for supporters who attacked protesters at his rallies, Refused to release his tax returns, Nor was Trump’s rampant sexism a secret. His public feuds with celebrities aside, the New York Times had already published a long article on times Trump was accused of crossing boundaries with women in his private life. And, of course, Trump had spent years publicly doubting that President Obama was born in the United States. This is not a complete list. But by the time Trump was picking a running mate, it was clear that he was a man with a history of bigoted, racist, sexist behavior and remarks. This is what Pence agreed to make palatable to the Republican establishment, to social conservatives, and to swing voters."