Democratic presidential hopefuls Bernie Sanders and Martin O'Malley were among the candidates who weighed in on the Iran deal Tuesday, following the party line and front-runner Hillary Clinton in support of the Obama administration's diplomacy.

The Iran deal will loom large over the campaign trail over the next 60 days, as Congress reviews the agreement and President Obama potentially vetoes legislation trying to reverse his handiwork.

"This is a victory for diplomacy over saber-rattling and could keep the United States from being drawn into another never-ending war in the Middle East," Vermont Sen. Bernie Sanders said in a statement. "I look forward to learning more about the complex details of this agreement to make sure that it is effective and strong."

Without having reviewed the agreement, O'Malley commended President Obama and Secretary of State John Kerry for their work, saying a "negotiated agreement, provided it's verifiable and enforceable, is the best path to a nuclear-free Iran." The former Maryland governor added that what he has heard of the deal sounds "promising."

In March, O'Malley warned a nuclear-armed Iran would present a "man made threat" to the United States. As governor, he supported state government sanctions against Iran in an attempt to slow the country's path to a nuclear bomb.

"I think that now Congress and all of us as citizens will have the opportunity to review this deal," O'Malley said Tuesday, adding "the bottom line in our consideration as a nation, I think, should be whether or not in fact there are the verifiable, enforceable mechanisms in place in this deal that would prevent Iran from developing a nuclear weapon."