Editor's note: Errol Louis is the host of "Inside City Hall," a nightly political show on NY1, a New York all-news channel. The opinions expressed in this commentary are solely those of the author.
(CNN) -- Politics abhors a vacuum, and the "Bridgegate scandal" engulfing Chris Christie has severely compromised the New Jersey governor's ability to launch a campaign for president, opening a space that Jeb Bush, the former Florida governor, seems likely to fill.
"The idea that he's the prohibitive front-runner is over" is how one Republican strategist described Christie's plight to the conservative National Review.
At stake is the future of the Republican Party, which has been divided for several years by a simmering fight between factions -- ultra-conservative Tea Party activists and more moderate establishment figures who control key party offices.
Christie and Bush are both frequently mentioned as mainstream candidates that the establishment would like to see run in 2016. But Christie's status as a party favorite has faltered, while Bush appears to be on the rise.
The contrast was on display at Saturday's White House Correspondents' Dinner, the high-profile, televised black-tie event in which the nation's media and political elites take satirical jabs at one another. Nobody got rougher treatment from the podium than Christie, especially from comedian Joel McHale, the evening's emcee.
"I promise that tonight will be both amusing and over quickly -- just like Chris Christie' s presidential bid," quipped McHale, who later harped on the apparently politically motivated traffic tie-up near the George Washington Bridge that has led to the firing and resignation of top Christie aides. "Finally, a politician willing to stand up to America's commuters," deadpanned McHale.
Bush, by contrast, escaped with a passing mention as a top presidential contender.
Christie's bad news shows up in polls that can't be dismissed as a joke. In a recent Washington Post/ABC News poll of all Americans, Bush ranked at the top of a list of Republican presidential contenders with a 14% showing; Christie's was 10%. A Fox News poll taken last month shows that among Republicans, Bush has a 52% approval rating compared with Christie's 46%.
After talking with more than 24 top Republican donors, reporters from The New York Times concluded in a recent article that "some of them are signaling to Mr. Christie's camp that, should Mr. Bush enter the race, their first loyalty would be to him, not to Mr. Christie."
That's a sea change from recent years, when Christie, a prodigious fund-raiser, wielded tight control over his New Jersey donors. According to Washington Post commentator Dan Balz, when candidate Mitt Romney came seeking support, in 2011, Christie said he told him: "If you raise money in New Jersey in any kind of aggressive, organized way, it's going to make it very unlikely that I'll be able to support you."
Things have changed. With Christie hemorrhaging support, a number of New Jersey heavy hitters are now openly agonizing over whether to stick with Christie or invest in a Bush candidacy. Bush brings multiple advantages: Having a father and brother who were presidents means there are legions of Republicans, across multiple generations, who owe personal and political loyalty to the closest thing the GOP has to a royal family.
On the hot-button issue of immigration reform, Bush has staked out an independent position, calling on Republicans to move away from "harsh rhetoric" on the issue and co-authoring a book on the subject -- an implicit recognition that winning the White House in 2016 will require support from Latinos and other pro-immigration voters.
Most importantly, Bush remains untouched by scandal, while Christie must cope with a scandal that just won't go away. Last week, an attorney for David Samson, a close adviser and mentor of Christie's, announced that Samson will not answer subpoenas from a state legislative committee investigating Bridgegate, citing his Fifth Amendment right against self-incrimination.
It's another crippling blow to Christie's presidential hopes. Samson, named by Christie to serve as chairman of the Port Authority of New York and New Jersey, oversaw the multibillion-dollar agency that runs the George Washington Bridge until he was forced to resign as the scandal unfolded.
Samson is the most prominent among several Christie aides who have quit or been fired and have now lawyered up. That means we'll see court fights around memos, meetings and other crucial evidence for months to come -- months during which Christie's nascent candidacy will continue to decline, leaving Bush looking like the white knight for which the Republican establishment has been waiting.