Donald Trump’s campaign is planning to drop up to $10 million on its biggest ad buy to date, hammering Democratic rival Hillary Clinton on her economic proposals in a slew of battleground states.

The Republican nominee is trying to make up for lost time in the ad wars, after being significantly outspent by Clinton on that front over the summer. But he’s also kept an active campaign schedule over the past week as his Democratic opponent mostly has stayed off the trail.

With its latest ad buy, the Trump campaign plans to cover nine battleground states.

They are: Ohio, Pennsylvania, North Carolina and Florida, where the campaign has already been on the air, along with New Hampshire, Virginia, Iowa, Colorado and Nevada.

His campaign’s second general election ad, unveiled Monday, hits Clinton on economic issues, claiming the middle-class would be “crushed” under a Clinton presidency amid tax increases and more spending.

“It’s more of the same, but worse,” the narrator says. “In Donald Trump’s America, working families get tax relief. Millions of new jobs created. Wages go up. … Change that makes America great again.”

Trump has so far been badly outspent by Clinton and groups supporting her. Since clinching her party's nomination in early June, Clinton has spent more than $77 million on television and radio advertising, largely targeting voters in battleground states, according to Kantar Media's political ad tracker.

Trump finally hit the airwaves earlier this month with his first ad, focused on immigration, and so far has only spent about $5 million.

Amid conflicting signals over his latest immigration platform, Trump now says he’ll deliver a detailed speech Wednesday on his proposal to crack down on illegal immigration.

The announcement came late Sunday in a tweet by the Republican presidential nominee after days of wavering -- and at least one canceled speech -- on a question central to his campaign: Whether he would, as he said in November, use a "deportation force" to eject the estimated 11 million people in the U.S. illegally.

Trump's immigration speech in Arizona will come after he and Clinton spent last week trading accusations on racial issues. Trump called Clinton "a bigot;" Clinton accused Trump of allowing hate groups to take over the Republican Party.

Clinton is starting this week by announcing her proposals for dealing with mental health issues. She is stressing the need to fully integrate mental health services into the U.S. health care system. Her plan stresses early diagnosis and intervention and calls for a national initiative for suicide prevention.

“Donald Trump’s reckless approach to business has devastated working families and communities. He will do and say whatever is in his interest, even if it means swindling working families to make millions for himself," Campaign Deputy Communications Director Christina Reynolds said in a statement. "Now Trump is promising the same reckless, self-centered approach to running the country’s economy – with large tax breaks for the wealthy, and a plan that independent experts say would cost millions of jobs."

Late Sunday, America's only African-American owned and operated national Christian television network also announced that its president and CEO, Bishop Wayne T. Jackson, would interview the Republican nominee Saturday in Detroit.

This comes as the Republican’s campaign vows the candidate, who has been appealing lately to minority voters for support, plans to go into African-American communities to seek their vote.

The new investment in advertising comes amid signs that Trump's lagging poll numbers may be improving against Clinton's following a campaign reboot.

Trump senior communications adviser Jason Miller said in a statement that the billionaire businessman's "positive message of economic opportunity is working and we see the national and battleground state polls all moving in the right direction."

"With Hillary Clinton off the campaign trail yet again this week and continuing to take many communities' votes for granted, we see this as the right time to show voters the benefits of an American economy under the leadership of Mr. Trump," he added.

Clinton will be spending much of the week in private fundraisers in the Hamptons, the wealthy enclaves of eastern Long Island, New York.

Fox News’ Nicholas Kalman and The Associated Press contributed to this report.