Eight presidential candidates are debating tonight at Oakland University in Rochester, Michigan. CNBC is broadcasting the debate beginning at 7 pm central time. Economic issues are supposed to be the focus of the discussion, but I imagine Herman Cain won’t be able to avoid some discussion of the spiraling sexual harassment allegations against him.

Former Massachusetts Governor Mitt Romney has a bit of a home-court advantage in Michigan, where his father was once governor. The Los Angeles Times published a damning report this week about Romney’s business practices at Bain Capital, which used “shell companies in two offshore tax havens to help eligible investors avoid paying U.S. taxes.” I expect Romney will be asked to comment on that report tonight.

I will update this post later with highlights, but meanwhile use this thread for any comments about the debate or the GOP presidential race.

UPDATE: A few thoughts are after the jump.

I missed the second half of last night’s debate, switching off after Rick Perry’s “oops.” But I saw enough to know that Mitt Romney was the big winner. He was calm, cool and collected, as usual. He projects tremendous confidence, which helped him gloss over his inconsistent position on whether the federal government should help the automobile manufacturers. He didn’t take the bait when asked whether he would fire a CEO facing sexual harassment allegations like those against Cain.

Second-place winner: Herman Cain. The audience booed when a panelist asked him about the alleged sexual harassment, and he forcefully defended his inane 9-9-9 plan. It may not have been the best debate performance I’ve seen by Cain; I don’t think it was wise to call former House Speaker Nancy Pelosi “Princess Nancy,” for instance. But any misstep on Cain’s part was overshadowed by Rick Perry’s devastating failure to remember the name of the third federal government agency he would eliminate.

I couldn’t help feeling a bit sorry for Perry. Almost everyone who’s done any public speaking has had the experience of forgetting something you should know. It’s painful to draw a mental blank like that when the word or person’s name is on the tip of your tongue. Unfortunately for Perry, he won’t get a pass for this understandable slip, because it reinforces a strong impression that he doesn’t know what he’s doing.

Perry’s Iowa campaign co-chairs, Bob Haus and Matt Whitaker, put on a brave face for the Des Moines Register today, but another Perry endorser was more honest:

“Oh, my God, it was just horrible. Just horrible,” said Hamilton County GOP Chairman Mark Greenfield, who has endorsed Perry. “I felt very bad for him. It happens. But it shouldn’t happen when you run for president.  It was very embarrassing for everyone.”

In the debate, the Texas governor and 2012 GOP presidential candidate said he would eliminate three departments – he named the commerce and education departments but failed to remember the third.

After several seconds that even supporters say were painful to watch, he gave up and said: “Sorry, oops.”

Perry eventually remembered the third: the energy department. […]

Greenfield said he’s still a Perry supporter, although he doesn’t see him staying in the race very much longer.

“At this point, I like his energy policies and a lot of other things, but I think it’s going to be tough after that debate debacle,” Greenfield said.

Of the second-tier candidates, I felt that Rick Santorum had the best night. He truly is the Joe Biden of this Republican field, and I would not be surprised to see him in the next president’s cabinet if Barack Obama is not re-elected.

Newt Gingrich is quite the crowd-pleaser. It would be funny if he managed to work his way back up to a top-three candidate.

I was shocked to hear Jon Huntsman criticize the “too big to fail” banks–was he suggesting that the government needs to do something to make them smaller? I wonder if he will pick up that theme as the campaign goes on.

Michele Bachmann and Ron Paul didn’t get a lot of air time last night and didn’t make much of an impression on me, compared to previous debates.

If you watched the debate, please share your thoughts.