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Of two potential Democratic successors to Barack Obama, one has a clear advantage in personal popularity: Hillary Clinton, whose favorability rating exceeds Joe Biden's by a hefty 19 percentage points in the latest ABC News/Washington Post poll.

Clinton, set to testify before Congress today about the Benghazi attack, appears undamaged by the security failure that led to the death of the U.S. ambassador to Libya: Sixty-seven percent of Americans see her favorably overall, numerically a new high in her long career in the public spotlight, and essentially unchanged in recent months.

See PDF with full results, charts and tables here. Biden, for his part, is seen favorably by many fewer Americans, 48 percent, vs. 37 percent unfavorable. That's a slight improvement over his break-even rating this summer during the presidential campaign, but worse than the consistent majority positive ratings he received immediately preceding and following the 2008 campaign.

The outgoing secretary of state also outperforms the vice president in intensity of sentiment in this poll, produced for ABC by Langer Research Associates. More than twice as many Americans see Clinton "strongly" favorably than strongly unfavorably - 35 vs. 14 percent - while Biden breaks even, 22 vs. 23 percent, in this measure.

Not only the visibility of Clinton's job as the country's top diplomat, but also its relative distance from the political battles in Washington, likely have benefited her image. Biden's position as vice president carries greater risk, given his closer proximity to the political fray. His reputation for sometimes controversial off-the-cuff comments likewise may have done him some harm.

Clinton also shapes up well against prominent Republicans, as measured in polling last summer. Sen. Marco Rubio (R-FL) was largely unknown; Jeb Bush, former governor of Florida, was underwater, 36-45 percent favorable-unfavorable; and the public divided essentially evenly on Rep. Paul Ryan (R-WI), the 2012 GOP nominee for vice president.

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GROUPS - Clinton is more popular than Biden across groups - notably, in partisan terms, among independents. She's seen more favorably than the vice president by 13 and 17 points among Democrats and Republicans, respectively, but by 23 points among independents, 65 percent vs. 42 percent for Biden. This gap reflects both more negative opinions of Biden and greater indecision about him.

Clinton's intensity advantage is apparent among partisans as well. Six in 10 of her own party's supporters see her strongly favorably, while 44 percent say so of Biden. Among Republicans, more have a strongly negative opinion of Biden than Clinton, 45 vs. 32 percent. And among independents, strongly positive views of Clinton outnumber intensely negative ones by 2-1, while for Biden, it's reversed.

Clinton's popularity surplus over Biden tops out among Hispanics (29 points, 73 vs. 44 percent favorable) in large part because many more have no opinion of Biden. By contrast, both are broadly popular among blacks - 83 and 79 percent, respectively. Clinton outdistances Biden by the same amount among whites as she does overall.

Notably, no gender gap is apparent: Both possible 2016 competitors do better among women than men - and Clinton outscores Biden by essentially the same amount among both sexes. And finally, for the record: Neither has expressed an intention actually to run for president.

METHODOLOGY - This ABC News/Washington Post poll was conducted by landline and cell phone Jan. 16-20, 2013, among a random national sample of 1,033 adults. Results have a margin of sampling error of 3.5 points. The survey was produced for ABC News by Langer Research Associates of New York, N.Y., with sampling, data collection and tabulation by SSRS/Social Science Research Solutions of Media, Pa.