Republican political strategist Karl Rove said time is running short for Republican presidential nominee Donald Trump to prosecute "precise lines of attack" on Kamala Harris — namely her policy "flip-flops" — while offering up new policy ideas that can win swing states.

Rove challenged Trump in a guest column for The Wall Street Journal on Wednesday.

"Mr. Trump needs to reset," he wrote.

"With less than 12 weeks to go, he's running out of time to settle on two or three ambitious second-term agenda items that will resonate with and reassure swing voters."