Poll: Michelle Obama would be Hillary’s strongest Dem rival in 2016
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If Michelle ObamaMichelle LeVaughn Robinson ObamaTrump rebukes Holder, Clinton with 'jobs not mobs' refrain Nikki Haley powerfully rebuts Trump Eric Trump calls out Holder on kicking comments: 'Who says this?' MORE decided to run for president in 2016, she would pose the most significant threat, among likely contenders, to Hillary ClintonHillary Diane Rodham ClintonO'Rourke's rise raises hopes for Texas Dems down ballot Gabbard considering 2020 run: report Claiming 'spousal privilege' to stonewall Congress MORE's chances of winning the Democratic nomination, according to a new Rasmussen poll.

A telephone survey of 1,000 likely voters conducted by the polling company found that in a hypothetical match-up between the current first lady and the former secretary of State, Clinton would best Obama 56 percent to 22 percent.

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That may seem like a significant margin, but according to the most recent RealClearPolitics polling average, Elizabeth WarrenElizabeth Ann WarrenDNA is irrelevant — Elizabeth Warren is simply not Cherokee The Hill's 12:30 Report — Trump seizes on immigrant 'caravan' for midterms | WHCA criticizes Trump for praising lawmaker who assaulted reporter | Trump takes harder line on Saudis Clinton aide: Chances 'highly unlikely' but 'not zero' Hillary will run for president again MORE, a popular hypothetical challenger to Clinton, receives only 12.5 percent to Clinton's 64 percent.

Sen. Bernie SandersBernard (Bernie) SandersSanders: Trump setting 'terrible example' for our children Gabbard considering 2020 run: report Sanders, Harris set to criss-cross Iowa MORE (I-Vt.), the only other major Democratic candidate in the race for president, is even further behind, with 7.4 percent. Former Maryland Gov. Martin O’Malley, who is expected to announce his bid on May 30, fares the worst against Clinton, with 1.2 percent of support from likely voters.

The first lady is highly unlikely to mount a presidential campaign, however. In fact, of the people surveyed by Rasmussen, just 14 percent thought she should run.

Still, 40 percent of black voters welcomed the idea of her running, and she bests Clinton among those voters, with 44 percent support among African-Americans compared with 36 percent for Clinton.

Obama herself recently joked about a possible October surprise, hinting to "Late Show" host David Letterman that the thought had crossed her mind.