As Donald Trump's poll numbers plummet, political observers are wondering if the Republican presidential candidate can get his campaign back on track Monday with what's billed as a major address before the Detroit Economic Club.

Trump is expected to "unveil his policy agenda for revitalizing the American economy," his campaign said in a press release.

The address comes at a critical point in the presidential campaign.

"It's a chance for him to get back on message, after a couple of weeks where it's been bad news after bad news after bad news for him," said Susan Demas, editor of the Inside Michigan Politics newsletter.

Since the Democratic and Republican conventions, Trump has created a series of controversies that have generated negative headlines -- from his battle with a Gold Star family; to his long delay in endorsing House Speaker Paul Ryan and U.S. Sens. John McCain and Kelly Ayotte in their primaries; to his comments on foreign policy that have some questioning his fitness to be president.

Meanwhile, while polls showed Trump and Hillary Clinton essentially tied after the GOP convention, Clinton has since jumped to a significant lead in a number of swing states. A Detroit News/WDIV-TV poll released Thursday had Clinton ahead by 9 points in Michigan and an EPIC-MRA poll released Friday had Clinton up by 11 points.

"Trump is cratering," Republican strategist Frank Luntz tweeted on Thursday. "He needs to overhaul his general-election strategy if he wants to have any hope of winning in 95 days."

The Fivethirtyeight.com website is now giving Clinton a 75 percent chance of winning in November, based on current polls, the economy and historical data.

"If Trump's actually going to have a chance to win," then he needs to use his Detroit speech to turn things around, said Dennis Lennox, a Detroit-area GOP strategist.

The event "presents a pivot opportunity for Trump to help him overcome two really bad weeks," Lennox said.

Lennox said there's a good chance that Trump can it pull it off, noting that Trump has done well in other circumstances he's given a formal speech, such as a March address on foreign policy before the American Israel Public Affairs Committee.

"Trump's biggest problem is that he has these rallies where he goes off message," Lennox said. "He's not a career politician, so message discipline for him is a little different than it is for someone like Clinton."

Monday's event also a chance for Trump to make inroads with Michigan voters, said Lennox and Demas.

"Trump has made a big deal about changing the map (of past presidential elections) and Michigan is a big deal for him," Demas said. "It's not a coincidence he's making a major address here.

"It's also a chance for him to press reset button and he could get a lot of positive press," she said.

Positive press may be the goal of the Trump campaign, but Steve Hood, a Democratic strategist who also has a radio show on AM 910 in Detroit, said Trump's speech could be upstaged by protesters.

"People are planning a serious, massive protest where they actually build a human wall and refuse to let people in," Hood said. The speech, originally planned to be at the Renaissance Center has been moved to Cobo Hall, citing security issues.

It also possible the protesters "will go too far and make Donald Trump sympathetic," Demas said.

Despite Trump's struggles in recent days, all three analysts interviewed said the presidential race remains in flux.

It's a "fluid period," Hood said. "There's still a chance Trump can win, and the Democrats are taking nothing for granted."

Demas agreed.

"Trump is trailing, but it's August," she said. "There's still time for him to make up ground."

But like Luntz, Demas said Trump needs to change his strategy.

"His not-politically-correct shtick that made him a winner in the primaries has caused him a lot of problems in the general election campaign," she said.

She said one of his biggest problems right now are questions being raised by prominent conservatives such as Charles Krauthammer and Joe Scarborough on whether Trump has the temperament to be the world's most powerful leader.

"We've been seeing a lot of prominent Republicans, prominent people from the foreign policy community, who are raising questions," she said. "People are very nervous about someone who seems so erratic."

Conservatives also have raised questions about Trump's economic stances, which have diverged from traditional Republican policies.

"The audience at the Detroit Economic Club is not likely to agree with Trump on immigration, on trade, on the fact that he's gone after the U.S. Chamber of Commerce," Demas said.

The GOP business community does like his plan to slash taxes, she said, but are much less enthusiastic about his call for massive spending on infrastructure projects.

Lennox agreed that Trump is not a traditional Republican, but said that helps explain his appeal.

Trump is moving the GOP beyond the "party of free trade and international intervention," Lennox said. "That's not your average Republican anymore."

Lennox thinks Trump has a real shot at winning in November, not just because of his populist message but also because of his opponent.

"I believe nothing brings Republicans together," he said, "than someone with the last name of Clinton."