Los Angeles Mayor and rising Democratic Party star Antonio Villaraigosa appeared before several thousand cheering Teamsters Union members and environmental advocates Tuesday in Oakland to speak on behalf of linitiatives aimed at improving air emissions coming from the Port of Oakland and to provide better working conditions for non-union truck drivers employed there.

While Villaraigosa faces the same issues back home from the Port of Los Angeles-Long Beach complex, the political significance of his appearance in Northern California would seem to further signal the seriousness of efforts to improve his statewide name-recognition as he contemplates running to succeed Arnold Schwarznegger as governor in 2010.

Speaking from a trailer-truck bed parked outside of the Oakland Convention Center, Villaraigosa was joined by Oakland Mayor Ron Dellums and state Treasurer Bill Lockyer in exalting the labor union members prior to their starting a short but noisy march to the Port of Oakland where yet another rally was held. The second event featured speeches by Teamsters General President James P. Hoffa, Attorney General Jerry Brown and Assemblyman Sandre Swanson (D-Oakland-Alameda.)

"We're showing the world that caring for the environment and supporting labor unions does not have to antithetical," Villaraigosa said in brief remarks. "What's good for labor is good for America and we should never forget that."

To be sure, port-generated air emissions directly impact poverty-stricken West Oakland. These emissions are thought to be chiefly responsible for the skyrocketing number of juvenile asthma cases reported there.

Discussions by the city-controlled Port of Oakland, the Teamsters, shipping companies and non union-represented truck drivers to possibly unionize the drivers and provide them with better, more efficient vehicles that produce fewer air emissions and particulates are under way.

After his short speech Villaraigosa was whisked away for a 4 p.m. plane ride back to Los Angeles. He was not available for comment at the rally.

Nevertheless, political observers said they doubted it was just coincidence that Villaraigosa would make an overtly political appearance in Oakland.

In fact, Tuesday's appearance marks the second time in less than a month he has traveled to Northern California. On June 25 Villaraigosa traveled to San Francisco where he hosted a fundraiser at the swanky downtown Neiman-Marcus department store.

Since then, of course, San Francisco Mayor Gavin Newsom has formed a gubernatorial exploratory committee and named New Hampshire Democratic heavyweight strategist Nick Clemons to head the effort.

If Villaraigosa takes the next step and forms his own exploratory committee, he will face a potentially crowded Democratic field vying for the governorship in 2010. In addition to Newsom, Villaraigosa potentially faces Attorney General and former governor Brown, Lt. Gov. Garamendi, Treasurer Lockyer as well as Controller Steve Westly, state Supt. of Instruction Jack O'Connell.

Potential GOP gubernatorial candidates include Insurance Commissioner Steve Poizner, former Hewlett-Packard CEO Carly Fiorina and former eBay Inc. President Meg Whitman.