President Barack Obama and the first lady highlighted Sunday’s rally on Ohio State’s Oval, but other Democratic politicians preceded the couple in an attempt to motivate voters before an election that experts say could return state and federal legislative control to Republicans.

“Democrats could lose up to five seats here in Ohio,” said Paul Beck, a political science professor at OSU. “If that happened, it of course would help the Republicans a lot.”

Mayor Michael B. Coleman emphasized the need for as many people to vote in the Nov. 2 election as did in 2008 when Obama was elected president.

“The marathon is not over,” he said, referencing both the Columbus Marathon he attended Sunday morning and the agenda Obama put into motion two years ago. “Let’s finish what we started.”

Other Democrats, including Gov. Ted Strickland and former Sen. John Glenn, echoed Coleman’s statements to a crowd that university police estimated at 35,000 people.

Beck said that although Democrats might face major congressional setbacks, the greatest threat is losing the governor’s seat.

“The governor race has a lot of implications of state funding of education,” he said.

John Kasich, Republican gubernatorial candidate for Ohio, would continue tax cuts that were frozen under Strickland and he would have to offset the $8 billion budget deficit by reducing spending in certain areas, including education, Beck said.

“K–12 and higher education are big budget items … if you take taxes off the table, you basically have to cut the budget — a total of $8 billion — out of state spending,” Beck said. “There’s just no other way.”

Rob Nichols, Kasich’s spokesman, said his boss thinks taxes are too high in Ohio and need to be cut.

“We are happy to let the voters of Ohio decide who is right,” Nichols said.

Lt. Gov. Lee Fisher called for clean energy, equal access to education, new jobs and living wages. He said Ohio will pave the way for national change.

“You can’t win America without winning Ohio,” he said. “You can’t win Ohio without winning central Ohio.”

Beck said that as the two parties drift ideologically further apart, the rally Sunday probably was effective in mobilizing already-active Democrats.

“The partisans who are there are among some of the most committed Democrats,” he said. “What it may do is encourage them to be even more active than they’ve already been, and it’s all rippled among millions of voters.”

But some who attended the rally felt that the Democratic speakers were too vague in describing their accomplishments.

Some of the politicians “just kept talking about how it’s moving in the right direction,” Columbus resident Carrie Woodward said. “But they didn’t really give any specifics.”

Lauren Hallow and Jami Jurich contributed as reporters to this article.