Secretary of State John Kerry is bringing the Obama administration's campaign for public and congressional support for the Iran nuclear deal to Philadelphia.

In a speech at the National Constitution Center, U.S. officials say Kerry will make the case that the agreement is the best way to prevent Iran from obtaining a nuclear weapon. He says critics have presented no reasonable alternative and that rejecting it would damage America's standing in the world. Kerry will also try to dispel what the administration says are a litany of "myths" about the deal.

The speech comes amid a bitter partisan battle over the agreement in Congress, where no Republicans support it. In a bid to project bipartisanship, Kerry will be introduced by former GOP Senator Richard Lugar of Indiana, a rare Republican who supports the deal.