Against all of that, Rudy Giuliani cannot rally any traditional GOP support. He won't rally the gun owners. Hillary may be just as likely to take our guns, but letting Rudy win as a Republican means that we no longer have a political party that will say "No" to the gun-grabbers. He won't rally the pro-lifers. Hillary may do less to protect life, but again, a Republican winning with Rudy's position means that pro-lifers no longer have a party to represent their beliefs. He can't rally those who understand that national security starts with border security because he stands against border security.
He'll make things closer in New York because he'll win more votes in the city than Republicans typically do. He'll just lose too many votes outside the city to tip the state to his side. He'll make California a little closer, but ultimately, the "first woman president" draw will keep California on Hillary's side. He might win New Jersey, but he'll lose Ohio because he can't win Reagan Democrats. Arkansas comes into play again in the South. The beltway folks in northern Virginia mean that Virginia is always in play, but this time, the Republican candidate won't get a boost from the rural areas of the state. The more traditional Republicans learn about what Rudy Giuliani really believes, the less likely they are to vote for him. States that have been solidly Republican will come back into play for the Democrats. Rudy Giuliani is not the ideal candidate to beat Hillary Clinton.
On top of all of these things, Rudy Giuliani will suppress Republican turnout overall. He doesn't represent the people who traditionally vote Republican. His "coattails" will likely help the Democrats more than the Republicans, so his nomination will mean the Democrats gaining more seats in Congress.
Bill
The cops who did that never said, "It's Giuliani time." That was a lie made up by Sharpton and the victims lawyers. Giuliani helped to save thousands of black lives by helping to dramatically reduce the murder rate in NYC. His anti-crime policies saved countless black women from becoming victims of rape. Countless numbers of black people in NYC avoided becoming victims of many other crimes as a result of Giuliani's anti-crime initiatives.