Democratic Sen. Barack Obama's presidential campaign is formally opening its Maine office in the state's largest city today.

Gov. John Baldacci, a former supporter of Sen. Hillary Clinton, will be joined by House Speaker Glenn Cummings and State Auditor Neria Douglass as they kick off the grand opening of "Obama's Campaign for Change" office in Portland.

Afterward, there'll be a voter registration drive.

Baldacci threw his support behind Obama after Clinton pulled out of the race. Since then, he joined other governors in discussing issues with Obama in Chicago.