Early endorsements -- so early that no Republican challenger has yet to announce -- seem to be a trend this year in Maryland's gubernatorial race.

Today, the Professional Firefighters of Maryland, which includes more than 7,000 emergency responders, announced its backing of Gov. Martin O'Malley, a Democrat. The election is almost eight months out, but the firefighters aren't the first on the scene.

In October, the Maryland State Education Association, the state's largest teachers union, announced its support, and endorsements from the Building Trades group and the Maryland League of Conservation Voters followed in January.

Unions traditionally support Democratic candidates, with endorsements and campaign contributions. An array of Democratic elected officials -- everyone from U.S. Senator Barbara Mikulski to Frederick City Alderman David Kip Koontz -- have also made clear they'll be stumping for O'Malley this fall.

Political observers, including those on O'Malley's campaign, are anticipating a November rematch with former Gov. Robert L. Ehrlich Jr., the only Republican governor of the Free State since Spiro Agnew in the 1960s. After one term, Ehlich lost to O'Malley in 2006. But a recent analysis says O'Malley is not necessarily "safe" in an Ehrlich rematch. Ehrlich has indicated he'll announce this month whether he'll get in the race.

From today's firefighters union endorsement:

"Governor O'Malley and Lieutenant Governor Brown have shown that public safety is and will continue to be a top priority for their administration," said Firefighters State President Mike Rund, according to a release from the O'Malley campaign. "This is clearly illustrated by their actions over the last four years, and we're proud to support them for re-election."