By Amanda Becker
WASHINGTON (Reuters) - The American Federation of Teachers on Saturday voted to endorse Democratic front-runner in the 2016 presidential primary race.
The American Federation of Teachers, which as the nation's second-largest education union represents 1.6 million members, is the first national union to endorse a 2016 presidential candidate.
The endorsement comes as Clinton prepares to deliver her first major address on the economy, which is being closely watched by labor leaders, many of whom have expressed support for U.S. Senator Bernie Sanders of Vermont, one of Clinton's rivals for the nomination.
"Hillary Clinton is a tested leader who shares our values, is supported by our members, and is prepared for a tough fight on behalf of students, families and communities," AFT President Randi Weingarten said in a statement, citing Clinton's record as a former first lady, U.S. senator and secretary of state.
Weingarten and Clinton are long-time friends and allies. The AFT endorsed Clinton in 2007 when organized labor split between supporting Clinton or now President Barack Obama. Clinton attended a meeting of the AFT's executive council last month to discuss her candidacy.
Clinton's campaign released a statement saying she was "honored" to receive the AFT's endorsement and "proud to stand with them to unleash the potential of every American."
Organized labor is a crucial base of support for the Democratic Party, with unions raising money and mobilizing voters for candidates.
The AFL-CIO, an umbrella group for 56 unions and of which AFT is a part, will host Clinton, Sanders and former Maryland Governor Martin O'Malley at a meeting of its executive council later this month.
The AFL-CIO has not said whether or when it will endorse a primary candidate. In 2008, when its member unions were split between Clinton and Obama, it backed Obama only once it became clear he was going to be the Democratic nominee. The National Education Association, the country's largest education union, sat out the endorsement process, backing neither Clinton nor Obama.
Clinton has made it clear that education will be a focus of her campaign. Her policy proposals related to hot-button issues such as charter schools, teacher tenure and standardized curriculum will be watched closely by teachers unions.
(Reporting By Amanda Becker)