(Reuters) - U.S. Vice President Kamala Harris on Wednesday plans to propose new incentives to boost domestic manufacturing, a day after her Republican election rival Donald Trump said he would seek to "take" factory jobs from other countries if elected.

In an appearance in the battleground state of Pennsylvania, the Democratic candidate in the Nov. 5 presidential election will lay out policies meant to build on her platform of homebuyer subsidies, small business tax breaks and a federal ban on grocery price gouging.

Harris is also expected to touch on her plan to work with the private sector and entrepreneurs to help grow the middle class in the speech at 3:15 pm ET (1915 GMT) at the Economic Club of Pittsburgh, according to a senior campaign official who spoke on condition of anonymity.

The two candidates have increasingly focused their campaign messaging on the economy, which Reuters/Ipsos polling shows is voters' top concern as Election Day approaches.

While Trump has proposed across-the-board tariffs on foreign-made goods to accomplish that goal - a proposal backed by a slim majority of voters - Harris is focusing on providing incentives for businesses to keep their operations in the U.S.

Harris in recent months has blunted Trump's advantage on the economy, with a Reuters/Ipsos poll published on Tuesday showing the Republican with a marginal 2 percentage point advantage on "the economy, unemployment and jobs," down from a 11 point lead in late July.

Harris has tried to paint herself as the best candidate for the American middle class, citing her own upbringing in contrast to Trump's wealth.

"For Donald Trump, our economy works best if it works for those who own the big skyscrapers. Not those who build them. Not those who wire them. Not those who mop the floors," she will say on Wednesday, according to the senior campaign official.

(Reporting by Gabriella Borter; Editing by Scott Malone and Lincoln Feast.)