The candidates know it: the union vote is one of the most important voices to back a candidate. This is because of the sheer number of union members and because of the economic funding that they can offer a campaign.

With Ohio’s primaries coming up, this Tuesday, both Democratic candidates are eagerly trying to secure more union support in this working-class state.

So, who will win the hearts of the unions?

Hillary Clinton has been running as a vanguard for America’s working, middle-class families, and she has received strong union support because of it.

She received the first national union endorsement, The United Transportation Union (UTU), back in August, while Barack Obama didn’t receive a national union endorsement until early in 2008 when Unite Here, a hospitality union, pledged its support.

But since then, Obama has picked up some momentum and snagged some important national union endorsements, including Teamsters, SEIU and the United Food and Commercial Workers.

These endorsements are important nationally, but will be especially important in Ohio, where 14 percent of the work force is unionized.

Wisconsin, which held its primary on Feb 19, has a very strong union base and similar demographics to Ohio.

But while Obama won in Wisconsin, in the current polls, he is trailing Sen. Clinton in Ohio by about six points, according to pollster.com.

How is this accounted for?

Some say that Clinton’s long-term connection with working-class families is pulling for her. Dating to her husband, the Clintons have been a friend to the working class. Obama, on the other hand, is a “newcomer” and hasn’t established a real connection with the unions, as of yet. But, like many others, some union members feel that his ability to excite people and organize the masses may be just what is needed to see reform that will benefit the working-class people.

Another possibility, is, when compared to Wisconsin, Ohio has a slightly less educated, lower income population– a bracket that has been a continual companion for Clinton.

But aside from what the polls say and what people expect to happen, it’s what the candidates stand for and what’s important to the people, that will determine who comes out with a win in Ohio, and the Democratic nomination.

When asked what the most important issues were for Ohio’s working-class, here is what some union members in Ohio said:

SEIU, endorsing Obama –

“He’s been able to bring together different people, black and white, different parts of the country, and that’s what it’s going to take to get health care and jobs,” said Gabe Kramer, 32, an SEIU organizer in an article on washingtonpost.com

United Transportation Union- the first union to endorse Sen. Clinton.

UTU International President Paul Thompson said in a written statement. “The UTU has a long history of picking winners early. Hillary will be a president that America’s working families can count on,” said UTU International President Paul Thompson in an article on CNN.

“Hillary Clinton’s record has been friendly to working men and women of this country. She consistently has endorsed the necessity of a strong middle class,” said the UTU’s incoming president, Mike Futhey Jr. in an article on Washingtonpost.

Unite Here- endorsing Obama

“Barack Obama has shown us that he understands our members’ struggles and dreams,” said D. Taylor, the Secretary-Treasurer of Culinary Local 226, in Nevada in an article on The Caucus, The New York Times political blog. “He stood with our union in every step of our recent contract negotiations and showed us that he too understands that organizing and bringing people together is how we move forward.”