WASHINGTON >> Even with voting already under way, President Barack Obama furiously worked the phones to urban-format radio stations Tuesday, arguing that his agenda would be “all at risk” if Republicans trampled Democrats.

“We need to keep moving forward, that’s why I need folks to vote today,” Obama told listeners to KPWR in Los Angeles.

Interrupting the music and chat of the station’s morning show, Obama phoned in from the Oval Office to acknowledge voter frustration with the recession-bound economy — and say that even though he’s not on the ballot, his agenda is.

“Are we taking the steps now to move us in the right direction, or are going to go back to the policies that got us into that mess in the first place?” he said.

Other calls went to radio stations in Las Vegas, Chicago and Jacksonville, Fla., with large African-American listenership. On Monday, Obama phoned a series of nationally syndicated radio programs.

With polls forecasting major GOP gains — possibly including a controlling majority in the House — Obama also scheduled a postelection news conference for 1 p.m. Wednesday in the White House East Room.

He strove to energize a key Democratic constituency hours after polls opened in the East and Midwest.

On the line to radio station KVEG in Las Vegas, Obama said, “I know things are still tough out there, but we finally have job growth again … It is all at risk if people don’t turn out and vote today.”

That call to the state with the nation’s highest jobless rate aimed to boost turnout for Senate Majority Leader Harry Reid, locked in a tight contest with Republican tea party-backed candidate Sharron Angle.

“Harry Reid has been my partner,” Obama said. “Every poll shows the race between Harry Reid and his opponent neck and neck. We know that if people who voted in 2008 turn out to vote in 2010, Harry will win. if they don’t turn out, he will lose.”

Obama said losing lawmakers like Reid would make it hard for him to “keep making improvements in the economy.”

“Across the board, thing have gotten better over the last two years,” Obama said on KPWR. “The question is, can we keep that up? But we can only keep it up if I’ve got some friends and allies in Congress and in the state houses.”

The host and others on the “Radio Big Boy” program were vocal in their support, and told the station’s listeners how “cool” it is to have Obama as president.

Toward the end, Obama joked, “I know that everybody’s thinking we need to get back to some music,” then turned serious.

“The future is yours to shape,” he said. “But if you don’t get involved, then somebody else is going to shape it for you.”