WASHINGTON (AP) - So far, it's so-so. That's how Republicans view their current field of presidential challengers, judging by a new poll from the Associated Press and GfK. Just over half the people surveyed say they're satisfied with the slate.

But as interest in the contest starts to build, there are already some winners and losers.

Congresswoman Michelle Bachmann of Minnesota, who has the support of a lot of tea party members, enjoyed a big boost in her favorability numbers after she turned in a smooth debate performance this month and joined the presidential race.

Former Minnesota Gov. Tim Pawlenty also made progress with Republicans, particularly among tea party supporters.

Mitt Romney held steady in the eyes of Republicans, but gained no ground, as he formally launched his campaign. He still has the highest favorability rating among announced candidates at 61 percent. Sarah Palin, who's still keeping people guessing, is holding steady at 63 percent.

As for Newt Gingrich, his favorability rating among Republicans fell from 61 percent to 43 percent in one month.

(Copyright 2011 by The Associated Press.  All Rights Reserved.)