DETROIT (WJBK) - Donald Trump and Hillary Clinton are preparing to face off for the first time ever.
The two presidential nominees are polling neck and neck heading into tonight's highly-anticipated primetime debate.
While some may be expecting pure fireworks tonight, one Michigan political analyst says both candidates will be challenged to produce a little bit of substance.
Ahead of the big night, Clinton is relying heavily on practice at the podium.
Insiders say she's been slinging responses at a Trump stand-in, trying to forecast what the candidate may say and do.
On the other hand, Trump is relying on campaign aides to prepare on issues the two will likely battle on.
If you're waiting for one-liners and zingers, you may be surprised.
"I think there's the expectation that (Trump's) going to be a showman, that he's going to come out with zingers. I actually think he's going to be more reserved. I think he's trying to make the case that he is commander-in-chief material, so I don't think he's going to go at Hillary Clinton as much, and I think that could help him," said Susan Demas, publisher of Inside Michigan Politics.
Demas says Clinton has to be ready for anything.
"I think she needs to come off as being the adult in the room -- presidential. She can't take the bait if Trump tries to incite her as he did during the Republican debates very successfully," she said.
The proverbial drumroll ahead of the debate is sounding on social media.
Clinton has not held back on her Twitter account, saying not a single living president is behind Trump and that he can't win tonight's debate by lying.
Trump hit back with a Bloomberg poll that puts him ahead in the race.
"Neither one of the candidates have good favorability numbers, actually quite the opposite," Demas said. "But with the other candidates in the field -- your Green Party and Libertarian candidates -- they aren't faring very well either. I think a lot of people tonight may be choosing between the lesser of two evils."
Anywhere from 80 to 100 million people are expected to watch, making this event the most-watched political debate in history.
"It's been a long time I think before debates actually turned an election, but this year could be an exception because there's certainly going to be a lot more people tuning in," Demas said.