No he can't: heckling, walkouts as Obama tries to rally Democrat vote

US President Barack Obama marched on the campaign trail for the first time this year with a rally to support the Democratic candidate for governor in the state of Maryland, but some in the crowd walked out as he spoke - underscoring his continuing unpopularity.

With his approval levels hovering around record lows, Obama has spent most of his campaign-related efforts this year raising money for struggling Democrats; the party risks losing control of the US Senate in the November 4 midterm elections.

Many candidates from the party have been wary of appearing with him during their election races because of his sagging popularity.

Not so Lieutenant Governor Anthony Brown of Maryland, who is running for governor, and Governor Pat Quinn of Illinois, who is running for re-election.

"You've got to vote," Obama repeated over and over at a rally for Brown in Upper Marlboro, Maryland, near Washington. Democrats have a history of not turning up to vote in midterm elections.

"There are no excuses. The future is up to us," Obama said.

Some 8,000 people turned out for the event, held in a noisy school gymnasium. But a steady stream of people walked out while he spoke, and a heckler interrupted his remarks.