Two powerful unions, one of which represents a large number of nursing home workers, are supporting Sen. Barack Obama (D-IL) for president.

The backing of the powerful Teamsters and the Service Employees International Union represents key endorsements for the candidate. The SEIU, which claims about 1.8 million members, is the largest union of healthcare workers. About 160,000 are nursing home employees.

“We have an enormous amount of respect for Sen. Clinton, but it’s now become clear members and leaders want to become part of an effort to elect Barack Obama the next president,” said Andy Stern, president of the SEIU.

Healthcare is a major topic of discussion in the 2008 election. According to a survey conducted by the Deloitte Center for Health Solutions, 79% of consumers think healthcare will be an important issue, and 46% described it as one of the top three issues affecting their vote.