GUY RAZ, HOST:
The top Republican presidential contenders are on stage tonight for a debate that is supposed to focus on the economy. But it's the first debate since news broke of multiple sexual harassment complaints against Herman Cain.
An NBC News-Wall Street Journal poll shows Cain's favorability among Republican primary voters unchanged over the past month. But the number of voters with a negative impression of him has more than tripled. Cain insists the controversy has helped his campaign.
NPR's Tamara Keith wanted to hear what some of Cain's own donors think.
TAMARA KEITH, BYLINE: When talking to people who've given to a candidate's campaign, you'd expect to find true believers.
MICHELE BOSACK: Something happened and I thought, this guy is special.
CARL PLOEGER: I listened to him talk. I liked what I heard and he seemed to be the kind of person that I would like to see be president of the United States.
PAM BENSON: Herman Cain just seemed to be the most logical and, to be honest with you, the non-politician.
KEITH: That was Michelle Bozak(ph), Carl Plager(ph) and Pam Benson(ph). They're among nearly two dozen Cain donors we've spoken to since Sharon Bialek first went public with her claims that Herman Cain made an unwanted sexual advance.
Benson is partially retired and lives in Buffalo Junction, Virginia.
BENSON: I just haven't believed it. In fact, this morning, I actually went online to donate again, just to show him that we were supporting him.
KEITH: Benson doesn't have a lot of faith in the media and she echoes a view held by many conservatives.
BENSON: It will take a lot more for me to abandon him. I mean, we've had a president who did a lot worse.
KEITH: Most donors we spoke with say they don't believe the charges and they will continue giving more money to his campaign. Two said they already had, but others are wavering ever so slightly. Carl Plager has been watching this closely and says Cain's press conference yesterday wasn't totally satisfying.
CARL PLAGER: Nobody still knows what's happened and it just boils down to who you believe.
KEITH: And who are you inclined to believe?
PLAGER: I'm still inclined to believe Herman.
KEITH: Plager says it would be a shame if this knocked Herman Cain out of the race. He's given Cain's campaign $1,500 so far this year and says he would like to give more, but...
PLAGER: I will probably wait another week or so to see if this story lingers on. If it lingers on another couple of weeks, it will probably damage him beyond repair.
KEITH: As much as he believes Cain should be president, Plager says it's most important to him that the Republican nominee has a real chance to go up against President Obama.
Michelle Bozak gave the Cain campaign $1,000 back in August. He's the first candidate she's ever given a substantial donation and she feels like the political establishment is just trying to make him go away. Still, she's not rushing back to donate again. She says she's going to give it a week.
MICHELLE BOZAK: If this sort of shakes out and it just looks like a take-down, I already am sensing that, but I'm not ready to make a call.
KEITH: If Bozak feels like Cain's side of the story holds up, she plans to give more, but she says, if it turns out there's any truth to the accusations...
BOZAK: I probably won't donate any more money, but I'll probably still be behind him because I still feel like he is the best person to help this country.
KEITH: This continued support is unsurprising from early primary season donors, says Michael Malbin, professor at the State University of New York, Albany and executive director of the Campaign Finance Institute. He warns that loyalty only goes so far.
MICHAEL MALBIN: Once the campaign starts spiraling downward, then even the true believers find that they have alternative sources for their disposable charitable money.
KEITH: Malbin isn't saying the Cain campaign is spiraling. That's not clear yet. Cain claims to have raised more than $1.1 million just since last week, which is about a fifth of what he had raised all year.
Tamara Keith, NPR News, Washington.