Richard Perry/The New York Times
Mitt Romney held a campaign event on Tuesday at a resort in Michigan, which he now thinks he can take from President Obama, who carried the state in 2008.

DeWITT, Mich. — Mitt Romney spent Tuesday baking pies here in this city just north of Lansing, but his campaign also sent a message to President Obama: Mr. Romney says he believes that Michigan is up for grabs in November, and if nothing else, his campaign plans to force Mr. Obama and the Democrats to spend time and money defending turf that, until recently, seemed safely in the blue.

Campaign aides say they believe that Michigan is, in fact, in play for Mr. Romney, who came of age here as the son of an auto executive turned governor of the state. They pointed to his full slate of events here Tuesday, the final swing of a five-day bus tour, as a sign of his seriousness about the state.
And if nothing else, Mr. Romney’s most recent dip into Michigan serves as a good test run in a state that at worst will force Mr. Obama and the Democrats to spend resources that they would prefer to deploy elsewhere.
As Mr. Romney said Monday night, in a brief conversation with reporters on his plane, “Who knows at this early stage, but I think Michigan’s a state I can win.”
When asked if the state had any special resonance, Mr. Romney added, “If I win in Michigan, then I become the president, and that would mean a lot to me personally.”
Mr. Romney also used his time in Michigan to address a rumor, first reported by ABC News, that had dogged him all day: that Senator Marco Rubio of Florida, a favorite of conservative Republicans, was not being vetted as a possible vice-presidential pick. At the final stop, Mr. Romney held an impromptu meeting with a small group of reporters, where he called the initial story “false.”
“Marco Rubio is being thoroughly vetted as part of our process,” Mr. Romney said.
The Romney campaign is using the summer to take stock of the electoral map and decide in which states to invest its time and resources. So far, it has two basic categories: a first tier of traditional swing states and historically Republican states that Mr. Obama won four years ago, and a second tier of states like Michigan, which it says it believes Mr. Obama needs to win to retain the White House, but where it believes changing demographics provide it with an opportunity.
“The practical reality is there are better opportunities that will be at the top of the list, but I think Michigan will be a viable place to play and a viable option,” said Saul Anuzis, a prominent Republican from Michigan. “If Michigan is going to be a potential state in play, you have to play here. He realizes that, his team realizes that, and I think it would be a political mistake not to seriously take a look at Michigan.”
Or, as Katie Packer Gage, Mr. Romney’s deputy campaign manager, put it, “There’s no road to the White House that doesn’t go through Michigan for Barack Obama.”
When Mr. Romney visited the state for a Republican conference on Mackinac Island in September, he told reporters that he would not be sentimental about the state and would compete here only if he saw a real opportunity.
Four years ago, Mr. Romney began his first presidential bid here, but this year the state has been the site of some of his major gaffes — a rally at Ford Field where he failed to fill most of the cavernous stadium and where he remarked that his wife, Ann, owns a couple of Cadillacs.
During the primary, he struggled with the state’s conservative base, but pulled out a victory over Rick Santorum. “There was a sense that the primary was to be survived, the general election is to be won,” said an adviser, speaking on the condition of anonymity in order to discuss the campaign’s thinking more freely. “In the campaign there was a sense that Michigan would be a better general election state than a primary state.”
Still, at a stop here on Tuesday, Mr. Romney acknowledged the long odds; Mr. Obama won the state with 57.4 percent of the vote in 2008.
“Now most people say that Michigan — out of touch, out of reach for a Republican, no way a Republican can win,” he said, before ticking down a list of Republican leaders in the state, including Gov. Rick Snyder, and adding, “Look, I see Republicans having been elected in this state.”
Neither Mr. Romney nor Mr. Obama has advertised in the state since the general election campaign began, according to the Kantar Media Campaign Media Analysis Group, but Mr. Romney’s campaign spent more than $2.5 million in Michigan during the primary contest. And outside Republican groups and pro-Romney “super PACs” have bought advertising time in the state to make it more competitive.
Other supporters of Mr. Romney also see reasons to be optimistic. Advisers say that the state has been hit hard by the recession and that his message of economic turnaround is likely to resonate with Reagan Democrats.
“He’s clearly going after the blue-collar Reagan class Democrat who has been suffering for the past four years,” Mr. Anuzis said. “It’s a very targeted strategic undertaking that he’s doing, and I think it’s working extremely effectively.”
Governor Snyder said Mr. Romney has a “good opportunity” to win the state, where the voters “are really focused on the topic of jobs and getting the economy going.”
But the Obama campaign is sure to hammer away at Mr. Romney’s opposition to the auto bailout, which the president got passed, helping to save the failing industry.
“This is a guy who loves cars, and I don’t think you’re going to convince the voters of Michigan that he doesn’t care about the industry,” Ms. Gage said. “He’s already forgotten more about cars and the American auto industry than anybody in the Obama administration will ever know.”
And, of course, a little hometown advantage never hurts. Waiting for Mr. Romney to take the stage here, Phyllis Hetherington wore two buttons: a tiny blue one from when George Romney ran for governor and a larger one for George’s son Mitt.
“This man represents Romney the governor,” she said, referring to Mitt Romney. “The acorn doesn’t fall far from the tree.”