( Reuters ) - With a week to go before Ohio's pivotal nominating contest, Hillary Clinton was fighting to hold onto a dwindling lead as rival Barack Obama worked to undercut her support, particularly among working class voters.
"They are really going at it with a frenzy," said Ohio State University political science professor Paul Beck.
The battles were playing out in a statewide swarm of mailers, television ads and in campaign events that have been drawing tens of thousands of would-be voters from all parts of this Midwestern state known for manufacturing and coal mining.
Clinton has said the results here and in Texas, which also holds its primary March 4, will be critical if she is to become the Democratic candidate who will face presumptive Republican nominee John McCain in the November election.
"If she were to lose one or the other, she would really have a hard time winning the nomination," said Beck.
Clinton and Obama square off Tuesday night in Cleveland for the last debate before the primary, which has 141 delegates at stake in Democratic party contest. Texas offers 228 delegates.
President Bill Clinton carried Ohio in both 1992 and 1996 elections and his wife's promises to create new jobs and provide universal health care garnered strong early support from working-class families hit by job losses. With more than 235,000 jobs gone since 2000, the state's unemployment rate of 6 percent is among the nation's highest.
"We have a lot of layoffs," said Ji Rawat, a 47-year-old sheetmetal worker with three children who showed up to support Clinton at a rally in Columbus. "People feel poor."
But Clinton's favor in the eyes of the working class took a hit last week when the 1.4 million-member International Brotherhood of Teamsters endorsed Obama, who is also pushing a message of job creation and health-care reform. That followed endorsements from the Service Employees International Union and the United Food and Commercial Workers Union, which represent a combined 3.2 million workers.
Obama's campaign coupled the endorsements with an attack positioning Clinton as a supporter of trade policies many workers believe dealt a death blow to their jobs.
Clinton's campaign has said Obama is distorting the facts and accused the Illinois senator of exploiting loopholes in campaign finance laws.
But a 21-point lead at mid-month has dropped to 9 points, with Clinton up 51 percent to 40 percent, according to a Quinnipiac University poll released Monday.
The signs of shifting sentiments, combined with a record of losing the last 10 straight state nominating contests in a row to Obama, has Clinton's campaign taking nothing for granted.
"It is going to be literally as much as we can get done in the next week," Clinton campaign spokesman Isaac Baker said of the final push in Ohio. "This is a very competitive race."
The campaign rolled out three television ads statewide this week, and is pushing thousands of volunteers onto the streets for door-to-door canvassing.
Campaigners are also encouraging Clinton supporters to cast ballots ahead of March 4, before they have a chance to be swayed by the 46-year-old Obama, who would be America's first black U.S. president and has been called a "rock star" politician who packs auditoriums with giddy crowds.
Clinton, who would be the first woman U.S. president, has also been playing up an endorsement from Gov. Ted Strickland, as well as the support of black congresswoman Stephanie Tubbs Jones.
Obama spokesman Dan Leistikow acknowledged Clinton's support in Ohio was "a huge challenge, but said Obama was gaining ground. The Illinois senator drew an estimated 11,000 to a rally in Cincinnati on Monday.
"The more voters get to know Senator Obama and hear his message the better he does," said Leistikow.
That was the case for Mark Lambert, a 41-year-old electrician at the General Motors plant in Moraine who has suffered a series of pay cuts and has pinned his hopes for an improved economy on Obama.
"I think he has the best chance of crossing the aisle and working with Republicans to get things done," said Lambert.