The bad news, the same poll finds Obama beating Romney, Cain and Perry in head-to-head matchups.

(The Hill) — Half of all Americans believe President Obama should not be re-elected, although the president leads all Republican challengers in head-to-head matchups according to a new AP-GfK poll.

The poll found that of all voters, 50 percent said Obama should not be given a second term, while 46 percent believed he should be, underscoring the president’s slide since the bitter debt-ceiling debate this summer.

But in a matchup with Mitt Romney, the Republican’s leading candidate, Obama led by a 48 percent to 45 percent margin. His leads were greater with Herman Cain (49 percent to 42 percent) and Rick Perry (51 percent to 42 percent), the other top-tier Republican candidates.