Senator Clinton is belatedly expanding her campaign efforts in Wisconsin in the hope that the state’s economically stressed, blue-collar workers will hand her a badly needed victory on Tuesday, blunting Senator Obama’s momentum as the Democratic presidential race heads into pivotal contests in Texas and Ohio next month.

Mrs. Clinton’s campaign announced yesterday that she will spend Saturday night through Tuesday morning in the Badger State, following on the heels of visits by President Clinton and their daughter, Chelsea. Senator Clinton also began television advertising there this week and put up an aggressive spot yesterday taunting Mr. Obama for dodging a debate.

“Both Democratic candidates were invited to a televised debate here in Wisconsin,” the commercial’s narrator says. “Hillary Clinton has said yes. Barack Obama hasn’t. Maybe he’d prefer to give speeches than have to answer questions.”

Buoyed by his recent string of wins, Mr. Obama swung through Wisconsin yesterday, making stops in three working-class, manufacturing centers, Janesville, Waukesha, and Racine.

In what may have been a retort to Mrs. Clinton’s new ad, the Illinois senator followed two of his rallies with question-and-answer sessions. At the Racine event, he asked sound technicians to shut off the usual upbeat post-speech music so that he could take questions from the crowd.

“The candidates have now decided to spend a good bit of time here,” a political science professor at the University of Wisconsin at Madison, Charles Franklin, said. “Clinton was a little bit later in making that decision, which suggested we really will be a little bit of a battleground for them.”

Outside advisers to Mrs. Clinton have been urging her to step up efforts in Wisconsin for days, but the campaign has seemed leery of making an all-out effort, perhaps out of fear that escalating the fight could simply give the former first lady more bad news if she loses. The state’s second largest population center, Madison, is home to groups Mrs. Clinton has struggled with, college students and upper-income professionals. “It’s the perfect Obama profile,” Mr. Franklin said.

However, the rest of the state could be more friendly territory for the New York senator. “It’s 37% Catholic in the Democratic primary,” the professor said. “Catholics have been very strongly favorable to Clinton. It’s kind of an old-style union state still and most of those kinds of unions have been favorable towards her.”

Mr. Franklin said the bellwether in the state will probably be conservative-leaning Democrats in the Milwaukee suburbs. If Mr. Obama can harness their dissatisfaction with Washington, he is likely to win the state. If they have more trust in Mrs. Clinton, she will probably emerge victorious, the professor said.

While money from a variety of outside groups flowed into Maryland and Virginia on Mrs. Clinton’s behalf, it is still unclear how much of a push Mrs. Clinton’s allies are planning to make in Wisconsin. Last week, the American Federation of Teachers pumped $200,000 into radio ads for Mrs. Clinton, but as of last night that was the only independent expenditure on her behalf reported in the state.

Getting a grasp on the current state of the race in Wisconsin is tricky. Only a few public polls have been conducted in recent weeks. One out Tuesday had Mr. Obama up by 11%. Another taken just after Super Tuesday showed Mrs. Clinton ahead by 9%.

Governor James Doyle, who is backing Mr. Obama, seemed to be upping the stakes, suggesting that Wisconsin was a measure of how the candidates will fare in the general election. “This is really a state where these two candidates can be tested,” he said in a conference call with reporters.

The Clinton campaign painted its increased efforts in Wisconsin yesterday as part of a broader effort to fight for every delegate. “We will be opening offices and hiring staff in all remaining states that are left to vote,” Mrs. Clinton’s field director, Guy Cecil, told reporters on a conference call yesterday.

Mr. Cecil said the campaign would try to win extra delegates in the upcoming states by tailoring its efforts to specific Congressional and state senate districts. “It’s not just about winning each state,” he said.

While the Democrats award delegates on a basis roughly proportional to the popular vote, most states do so on a district-by-district basis. That could help Mrs. Clinton and hurt Mr. Obama, because his strongest supporters tend to be clustered in urban areas and college towns.
On the stump yesterday, Mrs. Clinton toughened her message against Mr. Obama. “I am in the solutions business; my opponent is in the promises business,” she said in McAllen, Tex. yesterday. “People live in hope. We have hope. What we need is help and help is on the way,” she told a rally in San Antonio last night. “The question is not whether we will have change. The question is whether we will have progress that makes a difference in people’s lives.”

Mr. Obama did not respond directly, but suggested opposition to Mrs. Clinton would limit her ability to press issues like health care. “Senator Clinton’s got a pretty good health care plan,” he said. “The question is not who’s got the best plan right now. The question is who’s going to be able to actually get it done…You have to have a mandate where a sizable majority is going to be putting pressure on Congress saying this has to get done.”