TOLEDO — Donald Trump sought to build on a reed-thin lead during three campaign stops in Ohio on Thursday – and even suggested that the election should be scrapped.

“We should just cancel the election and just give it to Trump, right?” the Republican presidential nominee asked supporters while campaigning in this midwestern industrial city. “What are we even having it for? Her policies are so bad!”

Trump once again attacked the stamina of Democrat Hillary Clinton and said that he would reopen federal investigations into her use of a private email server when she was secretary of state and her family’s charitable foundation.

“Hillary Clinton put the office of secretary of state up for sale,” he said. “And if she got the chance, she’d put the Oval Office up for sale.”

Clinton, campaigning in North Carolina, sought to borrow from first lady Michelle Obama’s star power as her campaign warned supporters that the presidential election is likely to be closer than polls now appear.

“As Michelle reminds us, this election is about our kids and, in my case, our grandkids,” Clinton said. “We have a job to do. Starting right now, let’s come together. Let’s work together and be hopeful and optimistic and unified.”

Obama called Clinton a friend, and praised her qualifications and determination. “Hillary doesn’t play,” Obama said to laughter.

The first lady also warned supporters that Republicans are actively seeking to suppress turnout by making the election “so dirty and ugly that we don’t want any part of it.” She told the crowd: “When you hear folks talking about a global conspiracy and saying that this election is rigged, understand that they are trying to get you to stay home. They are trying to convince you that your vote doesn’t matter, that the outcome has already been determined and that you shouldn’t even bother to make your voice heard.”

Clinton is hoping that some of Obama’s magnetism and support among young people and African-Americans can help consolidate a lead in North Carolina. Obama has emerged as probably the Democrats’ most powerful and effective voice opposing Trump, and Clinton frequently quotes the first lady’s admonition to “go high” when critics “go low.”

In a sign of the power of Obama’s appeal, the Clinton campaign booked a huge stadium for Clinton’s first in-person campaign event with the first lady. The campaign cited a local fire marshal for the crowd estimate of 11,000 people at Lawrence Joel Veterans Memorial Coliseum, more than twice the size of most of the recent events Clinton has held alone.

Clinton appeared to joke about President and Michelle Obama’s reputation as a “cool” couple and the contrast with herself. She noted that she had enjoyed seeing the first couple dance.

“Ahhhh, one can only hope,” Clinton added in a wistful tone.

Campaigning earlier Thursday in Springfield, Ohio, Trump claimed again that Clinton appeared “tired” after the last two debates. He seemed to imply that she was on the verge of needing physical assistance.

Trump said Clinton is “a low-energy person.” Then, without presenting any evidence, he claimed that she was in bad physical shape after their most recent debates.

“I watched after the last debate and after the second debate. She was tired, wow. She walked off that stage, of course she had a lot of people around; they had a lot of people around her, which was smart,” Trump said.

No evidence has emerged that Clinton was suffering physically during or after the debates.

Trump also took aim at the Clintons’ charitable foundation and financial dealings, pointing to private communications released by the anti-secrecy group WikiLeaks, including a memo by top Bill Clinton aide Doug Band.

“The more emails WikiLeaks releases, the more lines between the Clinton Foundation, the secretary of state’s office and the Clintons’ personal finances, they all get blurred,” Trump said.

Band’s memo detailed what he called “Clinton Inc.,” a web of lucrative business ventures and overlapping charitable work. The memo was discovered in hacked emails from John Podesta, who is now chairman of Hillary Clinton’s campaign.

In an interview published Thursday by Billboard magazine, Bill Clinton weighed in on Trump’s criticisms, saying that the attacks on his foundation are frustrating. “It’s hard to hear because I know good and well that a lot of the people that are saying it know it’s not true. It’s an insult to all the people who have worked there,” he said. Trump was scheduled to make stops later Thursday in Toledo and Geneva, Ohio. His running mate, Indiana Gov. Mike Pence, visited Omaha and western Iowa, while Sen. Tim Kaine, D-Va., the Democratic vice presidential candidate, was also campaigning in Ohio.