At least three polls released this week showed President Obama's favorability rating hitting new lows.

In his first term, his favorable rating held steady even as his job approval rating slipped. But that's no longer true.

Fifty-two percent of Americans said they held an unfavorable view of Obama, according to a Gallup poll released Thursday. Forty-seven percent said they held a favorable opinion of him. The five-point net negative favorable rating is a new low for Obama in Gallup polling.

(Chart via Gallup)

The new CNN/ORC International poll showed something nearly identical, with Obama's favorable rating at 47 percent (a new low for Obama during his presidency in in CNN/ORC polling) and his unfavorable rating at 51 percent. A Bloomberg National poll pegged Obama's favorability rating at 44 percent.

So what gives? For starters, Obama has been going through yet another rough patch in his presidency lately.

The polls come as the Obama administration has been dealing with scandals that have rocked the VA and fallout from its decision to trade five Guantanamo detainees for a captured Army sergeant without consulting Congress. Plus, Republican groups and midterm election candidates continue to hammer the president over the federal health-care law.

Time is another factor. Presidents simply tend to be less popular in their second terms than their first. Take the chart from Gallup. It measures approval rating, which as we've noted is different from favorability, but still illustrates the point about declining numbers.

Ronald Reagan and Bill Clinton were the only two post-World War II presidents who saw an uptick in their second term numbers.