The fiscal conservative advocacy group Club for Growth said on Tuesday it was funding $1 million in advertisements attacking Republican Donald Trump in the early-nominating state of Iowa, the first concentrated campaign to dislodge the front runner in the race for the GOP nomination.

The ads will launch on Thursday, a day after the second official GOP debate in which Mr. Trump will again take the center podium. They publicize statements Mr. Trump has made in recent years in which he takes positions on health care, taxes, and other issues that the group says align him with Democratic front runner Hillary Clinton. One ad ends with a picture of Mr. Trump and his wife posing with the Clintons. The ads also seek to undermine Mr. Trump’s efforts to cast himself as an outsider to Washington, calling him “just another politician.”