Donald Trump is showing signs of having peaked, but he has been defying expectations all along. With Ben Carson passing him in some polls, and Carly Fiorina still looking strong, the only clear message is that the GOP electorate is enticed by the idea of a total outsider.

But the outsiders who look good in early polls often fade as Election Day grows nearer. That's why Marco Rubio is discussed in such glowing words these days, but Jeb Bush and Ted Cruz can't be counted out yet. Also, a Chris Christie Boom is a distinct possibility.

With three months to go until Iowa, here's who's making the biggest difference in the GOP field.

Timothy P. Carney, The Washington Examiner's senior political columnist, can be contacted at tcarney@washingtonexaminer.com. His column appears Tuesday and Thursday nights on washingtonexaminer.com.