In theory, the idea of an independent candidate running for president has broad appeal, but a few frequently mentioned contenders appear less alluring, according to a new Washington Post-ABC News poll.

Texas congressman Ron Paul, businessman Donald Trump and New York City Mayor Michael Bloomberg have all been mentioned as possible independent candidates, but their current favorable ratings suggest a long climb for all three.

Four in 10 or fewer Americans express favorable views of any of these potential candidates. While popularity does not necessarily equate to electability, it certainly helps to be liked by at least a majority of Americans.

Paul’s favorable ratings have been locked in at 32 percent for the past month, with 35 percent holding unfavorable views. Regardless of his favorable rating, he could very well shake up Republican plans to recover the White House in 2012 as an independent candidate. In a separate Post-ABC poll released Tuesday, Paul wins about one in five voters and secures a big advantage for President Obama in a potential three-way race including Obama and former Massachusetts governor Mitt Romney.

The problem for Paul in securing his party’s nomination is that his favorable ratings are less than glowing in the Republican base. Fewer than half of Republicans -- 43 percent -- rate him favorably and 35 percent see him unfavorably.

Donald Trump -- an erstwhile Republican who flirted with the idea of running in the GOP primary and as an independent candidate in the general election -- has a higher favorable rating than Paul at 40 percent but also higher unfavorable ratings at 48 percent.

Trump’s current ratings are a big change from a Post-ABC poll in January 2000 when he first dabbled in the idea of presidential politics. Back then, 70 percent had an unfavorable rating and just 20 percent favorable.

The remarkable switch-up for Trump has come courtesy of Republicans, only 14 percent of whom had favorable views in 2000. That number has now jumped to 56 percent, putting him 13 points above Paul in this group.  

Trump has about doubled his favorable ratings among independents too, from 21 to 41 percent. Democrats remain less enamored; 30 percent favorable, 61 percent unfavorable and similar to the 23 to 65 percent split in 2000.

Michael Bloomberg may have the best claim to appeal to all stripes of partisans. Before running for mayor of New York he was a declared Democrat, switched to the Republican Party from 2001 to 2007 and then declared as an independent in 2007.

His 30 percent favorable rating is lower than his New York billionaire neighbor Trump, but the mayor’s unfavorable rating of 26 percent is far lower with a large 44 percent offering no opinion. His appeal is a little more broad-based across party lines than Paul’s or Trump’s, but he is most popular among Democrats at 36 percent and peaks at 43 percent among liberal Democrats.

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