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As President Barack Obama readies for a return to the Iowa State Fairgrounds, his campaign is reminding voters that it was in that same spot where Republican rival Mitt Romney declared last year that "corporations are people."

Democrats slammed Romney's assertion as a gaffe that showed the former Massachusetts governor was aligned with big business.

The Obama campaign uses a clip of Romney being heckled as he made his corporation remarks in a web video released Thursday morning. The 30-second video then says Obama will be in the same spot Thursday, telling voters, "See you there."

Obama will hold a grass-roots campaign event at the fairgrounds Thursday evening. Earlier in the day, Obama will be seeking support for an election-year agenda to encourage renewable energy along with a more immediate prize: the state's up-for-grabs voters.

Obama was pushing Congress to support clean energy tax incentives, part of his congressional "to-do list" that he contends could help bolster the economy. The president has tried to portray congressional Republicans as obstructing his ideas to create jobs and said Republican challenger Mitt Romney would follow their lead.

The president was stopping in Iowa on Thursday after attending fundraisers in Colorado and California, returning to the state that launched his presidential campaign in 2008 and could play a pivotal role in whether he gets a second term. Iowa is a prime general election target for Romney, who narrowly lost the state's caucuses but expects to compete for the state's six electoral votes.

Obama was visiting TPI Composites in Newton, Iowa, a manufacturer of wind turbine blades that employs about 700 workers in a community that once served as headquarters for appliance maker Maytag Corp.

The president plans to urge Congress to renew the federal production tax credit for the wind industry, which is set to expire at the end of the year, and expand a tax credit that supports clean energy manufacturing.

Obama's "to-do list" includes a number of economic initiatives that the president has pushed previously, aiming to help manufacturers, strapped homeowners and veterans.

Republicans say the renewable energy tax credits have failed to spur the job creation that Democrats once promised and more concrete steps — like removing government barriers to energy production — would have a greater impact on the economy.

Obama was starting his day with a private fundraiser in northern California, his third fundraiser over two days in Silicon Valley.