In our first ranking of the very large and very unsettled 2016 Republican presidential field back in April of last year, we decided to not even include the name of one of the brightest stars in the GOP universe: Jeb Bush. We just didn’t think, at the time, that the former Florida governor and brother and son of presidents was all that interested in running.

But during 2013 and into this new year, we’ve gotten the sense, like many others, that things might be changing. So much so that we now consider Bush the leader of the field if he decides to run.

Why?

There are several reasons, and one of the most important does not have much to do with Bush, at least on the surface: Chris Christie’s bridge scandal.

To understand the potential importance of l’affaire bridge in determining whether Jeb Bush might run for president, we need to look back at the 2012 presidential cycle.

In the late summer of 2011, the Bush family surveyed the seemingly finalized Republican presidential primary field and apparently didn’t like what they saw. As reported by Dan Balz in Collision 2012 and Mark Halperin and John Heilemann in Double Down, Chris Christie received a phone call from former President George W. Bush in August 2011. Bush and Christie talked for 45 minutes about the pluses and minuses of running for president. Shortly thereafter, Christie’s wife, Mary Pat, got a call from former First Lady Barbara Bush, who described the benefits of raising a family in the White House. Christie also sat down with Bush consigliere Karl Rove and consulted with other Republican heavyweights, some close to the Bushes and some not.