On The Bubble: Whose White House Dreams Will Burst First?

The Iowa caucuses are known for hoisting the little-known hopeful to glory. But for each skyrocket that actually launched here, many more have fizzled on the pad.

The slick talkers auditioning for media gigs.

The household name whose prominence fails to translate.

The ambitious up-and-comer seeking name recognition for the future.

The nonpolitician who strikes a nerve the year before the election year.

After Iowa, the bell tolls for these.

For every Obama ...

When you think about Barack Obama breaking out in Iowa in 2008, think also of the candidates whose bids broke down: Sen. Joe Biden, D-Del., Gov. Bill Richardson, D-N.M., Sen. Chris Dodd, D-Conn. And that's not to mention John Edwards and Hillary Clinton, who fought on but never quite overcame what happened in Iowa.

You may recall that John Kerry caught the brass ring by winning the Iowa caucuses in 2004 and marching on to the Democratic nomination. Among others reaching for that ring that time were Howard Dean, Dick Gephardt, Dennis Kucinich, Wesley Clark, Joe Lieberman and Al Sharpton.

Do not expect a parade of once-hopefuls trudging to microphones to quit the very next day. There may be a few "no mas" moments this week, but there will be more the following week, after New Hampshire concurs (more or less) with the caucuses. Still others may wait to hear a third strike called in South Carolina later in the month.

It doesn't matter. The die will have been cast. Iowa does not so much kill candidacies outright as weaken them to the point of being on life support.

So who will be the first to acknowledge it?

The Democrats are momentarily exempt here. Bernie Sanders and Hillary Clinton will likely continue regardless of the results in Iowa and New Hampshire. (Martin O'Malley may decide to stick it out, especially with more debates on the horizon. He has never been an actual factor in the contest and can probably stay in the race as long as he can endure the put-downs.)

Clinton would suffer a huge blow if she loses Iowa badly. A close loss or virtual tie in Iowa, coupled with an expected defeat in New Hampshire, would still be survivable given her national numbers and standing in other states.

Sanders can easily survive a disappointment in Iowa, where he never expected to win.

So who will be first to go in the GOP?

The "Undercard" Players: In this cycle, with such a welter of notable hopefuls, the Republicans tried a two-tiered approach. They allowed most of the candidates to debate each other but created an undercard or "cocktail hour" debate for those at the low-end of the polls. A dubious solution from the start, the "kiddie table" began to seem like CPR for the barely breathing campaigns. ABC News has said there will not be an undercard at the Feb. 6 debate in New Hampshire, and that could be the end of it.

Carly Fiorina: While the undercard lived, it provided a brief boost to Fiorina, whose early performance there was enough to move her to the main stage. It was not enough to keep her there, however, and she has slumped to low single digits in national polls. Will she drop out? Given the key role the debates have played in her strategy, the end of the undercard augurs an end to her viability. But she will not be alone.

Rick Santorum will also lose his main purchase on public attention. Santorum actually won Iowa in 2012 and has spent plenty of time there since. But all that time has availed him little. Assuming he is an afterthought Monday night, he will be gone tomorrow. (See the New Hampshire proviso above.)

Mike Huckabee, who won Iowa in 2008 and stuck around longer than any of nominee John McCain's other rivals, has done a little better in Iowa than Santorum thus far. But he has never been a threat to the top four. He has little visibility in New Hampshire, but he may wish to plow on into South Carolina, where his team still blames Fred Thompson for costing him the Palmetto State in 2008.

Jim Gilmore, who did not even make it to the kiddie table through most of debate season, may remain an official candidate but will matter less than ever. If he drops out, don't look for it on Page 1.

Rand Paul: It seems hard to remember now, but when Paul declared for president last year, he had already been on the cover of Time magazine several times since his first Senate election in 2010. He was, as Time put it, the new face of the Grand Old Party. Paul was, at first, regarded as a first-tier contender, yet by year's end he had been dropped from the main stage debate and had refused to participate in the undercard. Last year, Paul persuaded legislators to change Kentucky law to allow him to seek the White House and re-election to the Senate. The latter race will need his immediate attention after Iowa and New Hampshire.

Ben Carson: A respected brain surgeon and successful inspirational speaker, Carson overcame a faltering start as a candidate to become the early leader in Iowa polls. His career story, mild demeanor and clear commitment to his faith appealed to the evangelical voters who have often dominated GOP caucuses there. But late in the fall, terrorist massacres in Paris and Southern California refocused voter concerns. Carson seemed lost in the new landscape, and his support decayed. His campaign infrastructure teetered on collapse, and his debate performances faded even more. In Iowa, his voters largely decamped to Cruz. Carson has no prospects in New Hampshire, but might stick around for South Carolina.

Chris Christie: The New Jersey governor entered this cycle with known problems back home, including the bridge-closing affair and various state fiscal woes. But his worst problem was that Donald Trump utterly expropriated the bombastic tough-guy style that is Christie's stock in trade. He has always had his eye on New Hampshire, so losing Iowa won't be fatal. But the lack of any bump out of Iowa will mean Christie is back in the pack, battling three or four others for second place in New Hampshire. If he's second in the Granite State, or third after Cruz, he stands a chance of becoming the candidate the anti-Trump forces rally behind.

John Kasich: Another governor who fit the profile of past Republican winners well was Kasich, the current and popular governor of pivotal swing state Ohio. Kasich has not caught on with Iowans, however, and needs to survive a low finish there to break through in New Hampshire. Like Christie, he has his hopes pinned to a top-three finish there, and he has had a good January in that state. If it doesn't work out that way, the next question is how long Kasich should stick around if he wants to be vice president. Why wouldn't he want to be vice president? After Marco Rubio, Kasich offers the most as a running mate for any of the remaining prospective nominees.

Jeb Bush: The former Florida governor and dynastic insider may be the ultimate case of a front-runner who never really got out front (and took a long time to start really running). Bush still hopes the fierce rivalry of Cruz and Rubio will weaken both, and Trump will somehow disqualify himself. If those things happen, Bush may still be the most logical choice for establishment Republicans, officeholders and major donors to fall back on.

The first President Bush survived a third-place embarrassment in Iowa in 1988, and the younger George Bush got past a disastrous showing in New Hampshire in 2000. So there is resilience built in this campaign. The Bushes will battle on at least through February. The Super Tuesday primaries on March 1 could mean rebirth — or the end of the road. In any event, like Christie and Kasich, Bush is loath to leave the field and concede the contest to Trump and the two sons of Cuban emigres arguing about who's toughest on immigration.

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