IOWA CITY, Iowa — President Barack Obama issued a dare to Republicans who are vowing to repeal his new health care law, telling them today to "Go for it" and see how well they do with voters in November.

"Be my guest," Obama said in the first of many planned appearances to sell the revamp before fall congressional elections. "If they want to have that fight, we can have it. Because I don't believe the American people are going to put the insurance industry back in the driver's seat."

With emotions raw around the nation over this week's Democrats-only vote to approve the nearly $1 trillion redesign of the health care system, Obama took the opposition to task for "plenty of fear-mongering, plenty of overheated rhetoric."

"If you turn on the news, you'll see that those same folks are still shouting about how it's going to be the end of the world because this bill passed," said Obama, returning to the college town where, as a presidential candidate three years ago, he unveiled his plan to provide health care for all.

No Republican lawmakers voted for the 10-year, sweeping package that Obama signed Tuesday and will shape how almost every American will receive and pay for medical treatment.