Crunch Time: What GOP Candidates Need to Prove at the New Hampshire Debate

It’s a do-or-die moment for several campaigns.

— MANCHESTER, NH -- Iowa has sent New Hampshire voters a gift, of sorts: a slightly winnowed field.

So where will we see fireworks?

Trump and Cruz

Based on the fraud committed by Senator Ted Cruz during the Iowa Caucus, either a new election should take place or Cruz results nullified. — Donald J. Trump (@realDonaldTrump) February 3, 2016

It’s beyond unlikely that Trump will get his wish, so a debate brawl might be the next best thing.

The Cruz camp seems ready for it. In a statement, spokesman Rick Tyler said “reality just hit the reality TV star – he lost Iowa and now nobody is talking about him, so he’s popping off Twitter. There are support groups for Twitter addiction, perhaps he should find is local chapter.”

Cruz and Rubio

“Basically, his entire campaign is an Iowa campaign,” Rubio told ABC News during a lunch break Tuesday. “We’ve been running a full-time campaign everywhere.”

Cruz, meanwhile, was zig-zagging the country Tuesday, giving an impromptu news conference aboard his plane, “Constitution One.”

Asked about Rubio, Cruz demurred. “Where I’m going to keep my focus, is my positive optimistic conservative message,” he said.

The two have sparred repeatedly over immigration and national defense. Expect each of them to appeal to Granite Staters to give them a second or third look in the wake of their success.

Rubio and Everyone Else

The Rubio campaign has declared it a “three-man race” between Rubio, Cruz and Trump.

New Hampshire voters awoke this morning to a full-page ad in the state’s largest newspaper, touting endorsements from Florida House speakers who decided to back Bush, not Rubio. Ads from super PACs like Right to Rise, which supports Bush, have put out attack spots focusing on Rubio’s personal credit cards.

New Jersey Gov. Chris Christie, meanwhile, has continued to tie Rubio’s leadership experience to President Obama.

“Fool me once, shame on you. Fool me twice, shame on me,” Christie told a New Hampshire crowd, describing the dangers of promoting a first-term senator to the Oval Office.

Ohio Gov. John Kasich has displayed a relentlessly positive attitude on the New Hampshire campaign circuit, but has shown a willingness to engage on the debate stage. He has also shown a distaste for his rivals’ ads, calling on Bush and Christie to take “negative crap” off the air.

Between Rubio and the three governors, it’s likely only one or two emerge from New Hampshire as the “establishment” alternative to Trump and Cruz. Six days from the primary, more than 20 percent of Granite State Republicans say they’re undecided.

ABC News will announce the lineup for the Republican debate Thursday.

ABC News' Jessica Hopper and Jordyn Phelps contributed reporting.

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