O'Malley squeaks into next Dem debate
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Martin O'Malley has squeaked into this Sunday night's NBC News/YouTube Democratic presidential debate after poor poll numbers put his status in doubt.

NBC News announced Thursday that the former Maryland governor will join Hillary ClintonHillary Rodham ClintonWarren: 'Today is a great day... but I'm not doing a touchdown dance' Hollywood stars weigh in on GOP pulling healthcare bill Hillary Clinton: Today was a victory, 'but this fight isn't over yet' MORE and Sen. Bernie SandersBernie SandersWarren: 'Today is a great day... but I'm not doing a touchdown dance' Sanders: Canceled ObamaCare repeal vote 'major victory' for working class Stunning polls show Sanders soaring while 'TrumpCare' crashes MORE (I-Vt.) on stage in South Carolina.

O'Malley needed to hit 5 percent in averages of qualifying national polls or those from Iowa or New Hampshire. From the moment the network announced the criteria last week, it became clear that his only avenue would be Iowa.

In tweets from their campaign staffs, Clinton and Sanders both called for O'Malley to be included in the debate hours after the criteria was announced.

NBC's press release did not specify which polls it considered as the five most recent in Iowa, as O'Malley appears to have just barely made it past that threshold. NBC told The Hill last week that it would round up from 4.5 percent if necessary.

In the four most recent qualifying Iowa polls — Quinnipiac University, NBC/Wall Street Journal/Marist, Des Moines Register/Bloomberg Politics, and Fox News — O'Malley averaged exactly 4.5 percent. But there was a tie for the fifth most recent poll, as a Loras College poll and another Quinnipiac poll were both released on Dec. 15. Including the Loras poll's 4 percent would have put O'Malley at 4.4 percent, while including the Quinnipiac poll's 6 percent would put him above the threshold.

Missing the debate stage would have been a blow to the O'Malley campaign, which has struggled to gain traction as the progressive alternative to Clinton. National polls as well as early state surveys suggest a two-person race between Clinton and Sanders, with O'Malley polling far below the pair.

—This report was updated at 12:34 p.m.