With President Obama’s approval ratings mired near career lows, the number of Americans holding favorable impressions of him has – for the first time in his presidency – sagged under 50 percent, according to Washington Post-ABC News polls. Barely more than one in five now hold “strongly” positive views, down significantly since the spring.

In the poll – a new weekly look at who is up and who is down on this basic measure of public sentiment – 47 percent say they view Obama favorably, but just as many, 46 percent, view him unfavorably. For the first time, those with intensely negative impressions outnumber his strong backers.

For Texas Gov. Rick Perry and former Massachusetts governor Mitt Romney, Obama’s top Republican challengers, the first hurdle is familiarity. Fully 46 percent of those polled express no opinion about Perry, and nearly as many – 37 percent have no thoughts on Romney.

Among those who do have an opinion of Romney, just as many view him unfavorably as favorably. Perry’s numbers tilt negative, with 31 percent of all Americans expressing unfavorable views, compared with 23 percent who have positive ones. Perry’s strong detractors outnumber his fierce supporters by better than 2 to 1 (19 to 7 percent).

Conservative Republicans express broadly favorable views of both Romney and Perry, with the Texas governor having ample head room in this core group: 38 percent of conservative Republicans do not yet offer a rating for Perry.

But casting ahead to a potential general election showdown with Obama – at least among independents--Romney is better positioned: independents split 35 percent favorable to 30 percent unfavorable. For Perry, independents are 23 percent favorable; 36 percent unfavorable.

The opportunity for the Republicans is apparent. Nearly half of independents – 48 percent – hold unfavorable views of Obama. The number of independents with strongly favorable views has sagged to a new low of 14 percent, with twice as many – 28 percent – expressing strongly unfavorable ones.

Obama’s most solid backers have slipped notably on this score as well.

African Americans continue to view the president favorably in overwhelming numbers, but the proportion expressing strongly positive views has dropped 25 points since mid-April. Five months ago, 83 percent of African Americans held strongly favorable impressions of Obama. In the new poll, the number doing so is 58 percent.

Similarly, for the first time since he’s been in office, Obama’s favorable rating has slipped below 50 percent among those aged 18 to 29, with as many holding strongly unfavorable as strongly favorable views (21 to 18 percent). Strongly favorable views among all liberal Democrats are down from 69 percent in April to 52 percent now.

The poll was conducted September 14 to 18 among a random national sample of 1,013 adults. The results have a margin of sampling error of plus or minus 3.5 percentage points.

Read the full poll results.

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