They visited Green Bay within hours of each other on Thursday: a Wisconsin governor and a U.S. president, a Republican and a Democrat. Both men have won landslides in Wisconsin.

Now, both desperately wanted their side to win a squeaker.

“We’re ground zero, yet again,” Gov. Scott Walker (R) told Republican volunteers in the afternoon at a “victory center” run by Mitt Romney’s campaign in the Green Bay suburb of Allouez. “We can shock the world again.”

“I need you, Wisconsin,” President Obama said during a rally that morning at the Green Bay airport. “We’ve come too far to turn back now.”

Wisconsin is the Ohio that you may not know about. Just days before the election, this state is being blanketed by TV ads and hopscotched by candidates, as Romney tries to deny Obama a vital piece of the Democrat’s electoral strategy.

Explore the 2012 electoral map and view historical results and demographics

It’s an odd role for this traditionally blue state, where in 2008 Obama won by a stunning 14 points. But since then, the state has lurched to the right, electing the conservative Walker in 2010, then defeating an effort to recall him this summer.

Now, just as Wisconsin symbolized the euphoric roll of Obama’s first presidential campaign, it has come to symbolize the grim, grinding numbers game of his second. To win in Wisconsin, Obama’s task is to make sure he only loses most of his landslide, and not quite all of it.

To that end, he will be back Saturday. And Monday.

Understanding the last-minute fight for Wisconsin requires understanding that — this year — there are swing states, and then there are swing states. In all, between eight and 11 states may be toss-ups, within reach for Romney and Obama.

But Obama needs to win only three of them to take the presidency.

Two of these crucial three are old-time electoral battlegrounds: Nevada and Ohio. The other is Wisconsin — a theoretical swing state, which hasn’t actually swung since 1988. Democratic candidates have won it ever since, and Obama won it bigger than any Democrat since Lyndon B. Johnson in 1964.

Right now, most state polls show Obama ahead in Wisconsin. But Romney’s camp says it can win. In a call with reporters Wednesday, Romney political director Rich Beeson listed Wisconsin among the states where Obama’s swing-state advantage was crumbling.

“Right now,” Beeson said, “their firewall is burning.”

Now both campaigns have settled on the same two-step strategy. To win the election, you need Wisconsin. And to win Wisconsin, you need the Green Bay region — specifically, a swath of three fickle counties that are the battleground of the battleground.

In these places, state political hands say, a history of labor unions pulls voters toward the Democrats. But Catholic social values and gun ownership pull them toward the GOP.

On Wednesday, Romney running mate Rep. Paul Ryan — a native of Janesville, in another part of the state — was in Green Bay. And he was laying on the Wisconsin like sweet creamery butter.

Ryan took the stage in a University of Wisconsin Badgers jacket. In the first minute of his speech, he mentioned the Badgers, the rutting of local deer and the cover ­of hunter’s-camouflage-and-blaze-orange he kept on his iPhone. In the second minute, Ryan mentioned the only Wisconsin icons he’d left out in the first: the Green Bay Packers and cheese.

“I see your cheeseheads,” he told the crowd, many of whom were wearing the plastic cheese wedges on their heads. “It makes me homesick and hungry at once.”

On Thursday morning, Obama spoke a few miles away, on the tarmac at Green Bay’s airport. Obama conceded he is a Chicago Bears fan, but he brought an actual Packer — defensive back Charles Woodson — to vouch for him. “Let’s vote for the one candidate who has everybody’s best interests at heart, not just a very few,” Woodson said, according to news reports.

Meanwhile, the Green Bay TV market has been saturated by nearly 10,000 political ads, $4 million worth. And both campaigns have tried to wring one last push out of their local “ground game operations,” which are both practiced and exhausted after months of battling over Walker’s conservative agenda.

On Obama’s side, it has been difficult to reawaken Democratic enthusiasm after two defeats by Walker. That was clear on Halloween, when campaign workers were trying to stop passing students at the University of Wisconsin at Oshkosh. The students mainly kept walking. Then, a stroke of good luck. 

Zombies attacked.

More than 100 students staggered into the student union in torn clothes and bloody makeup, playing along with a professor’s Halloween prank for 25 points of extra credit in microbiology.

The zombies hit a bottleneck. The undead started backing up.

“Who wants a sign?” Obama worker Chris Walloch asked them. Students either avoided eye contact or shook their heads “no.”

“Zombies for Barack!” Walloch yelled. Nothing. Just two red-smeared students stayed behind to ask about voting. “This,” Walloch said, “is the weirdest experience I’ve ever had.”

Across town at the Winnebago County Republican headquarters, there was a feeling of momentum — and a worry that it might not be enough. GOP membership nearly doubled here. The party now has enough donations to rent an office on Main Street.

“The votes are there. We know from Scott Walker that the votes are there,” said Diane Malecki, a volunteer, in an office adorned with Ronald Reagan portraits. “And if we can get them to the polls, then Romney can win Wisconsin."

But those votes can still be painfully hard to get. Among Malecki’s volunteers are Craig and Donna Rider, retirees who have spent weeks working on just one vote: their friend and fellow Catholic Bob Dietsche. They ask: What about same-sex marriage? What about abortion? “If you’re Catholic, you cannot in good conscience vote for that,” Donna said.

It was right out of the Romney campaign’s playbook for Wisconsin. At the GOP office, the Riders thought they might be moving him.

They weren’t. Dietsche, a retired teacher, is an anti-abortion Catholic. He’s disappointed with Obama and thinks he hasn’t done enough to sell his ideas. But he’s sticking with him. “Definitely,” ­Dietsche said. “Because the alternative is not very good.” He wishes Romney had done more to rebuke fellow Republican Rep. Todd Akin (Mo.), the Senate candidate who said that women’s bodies would ”shut down” pregnancies caused by rape.