US President Barack Obama will Friday step up his mid-term election campaign and appeal to voters dismayed by the stuttering economy with his first White House press conference since May.

Obama scheduled the appearance at 11:00 am (1500 GMT) to press home the case on his recovery plans, but the event may be overtaken by the fast-moving controversy over a Florida pastor's on-hold threat to torch the Koran.

The president's appearance comes at the end of a week in which Obama has tried to reframe the political climate ahead of November's congressional polls in which his Democrats fear heavy losses.

He admitted in a television interview Wednesday that his party would not do well in the election if it became a judgment on the state of the economy in the wake of the worst financial meltdown in decades.

"If the election is a referendum on are people satisfied about the economy as it currently is, then we're not going to do well," Obama told ABC News.

"I think everybody feels like this economy needs to do better than it's been doing," Obama said.

"My challenge, and the challenge of every Democratic candidate who's out there is just making sure the people understand there's a choice here."

A Quinnipiac University poll published on Thursday made uncomfortable reading for the administration, with voters disapproving of his handling of the economy -- the major election issue -- by 56 to 39 percent.

On Wednesday in Ohio, Obama mounted a staunch defense of his policies, which he says staved off an even deeper recession, and slammed Republicans who he said want to revive the policies that triggered the meltdown.

"It's still fear versus hope, the past versus the future," Obama said, pleading with voters to choose "moving forward" with him rather than "sliding backward" with Republicans.

As Obama seeks to convince Americans that his policy prescriptions for moving on from the economic crisis are working, an administration official late Thursday confirmed Obama's choice of economics professor Austan Goolsbee to chair his Council of Economic Advisors.

Goolsbee will serve as the president's top economist in place of Christina Romer, who left last week to return to the academic world, the administration official said on condition of anonymity.

Goolsbee is currently serving as chief economist on the president's Economic Recovery Advisory Board, which Obama set up to provide outside and independent advice as he navigates the economic recovery.

At his press conference Obama will also likely be pressed on the row sparked by Florida pastor Terry Jones's threat to torch 200 Korans on Saturday, the anniversary of the September 11 attacks, a plan he has since put on hold.

The president warned in the ABC interview, given before the pastor stood down, that the move, which sparked outrage in Muslim world, posed a grave danger to US security and troops abroad.

"You know, you could have serious violence in places like Pakistan or Afghanistan," Obama said.

"This is a recruitment bonanza for Al Qaeda."

Reporters may also ask Obama to expand on the launch under US auspices last week of direct talks between Israel and the Palestinians and his stewardship of the war in Afghanistan and Iran's nuclear challenge.