WASHINGTON, D.C. (Sept. 6, 2015) -- As lawmakers return to Capitol Hill this week, they do so knowing Congress won't be able to block the highly controversial nuclear deal with Iran.
CBS News reported Sunday the deal received public support from two prominent political figures - former Secretary of State Colin Powell, a Republican, and Democratic National Committee Chairwoman, Florida Rep. Debbie Wasserman Schultz.
Last week Sen. Barbara Mikulski (D-Maryland) became the 34th Democrat to announce her support for the deal, giving President Obama enough support in the Senate to sustain his veto if Republicans pass a resolution against the agreement.
No GOP senators have said they will support the deal.
Still hundreds-of-thousands of dollars are still being spent to publicly sway key Democratic votes, like Sen. Joe Donnelly (D-Indiana).
"Joe Donnelly broke his promise," a TV ad says running in Indianapolis by the Republican Jewish Coalition.
In an interview with CBS4, Donnelly said his position hasn't changed.
"I'm continuing to move forward in the views I've had, in trying to make sure we don't put our men and women in harm's way before we necessarily have to," he said. "And so as far as I can see, there has been no better alternative than this deal."
When asked if any Obama administration officials lobbied him for his vote, Donnelly said, "My vote belongs to the people of Indiana, and so whether it's an administration or whether it's anyone else is not of interest to me. What's of interest to me is Hoosiers and Hoosier families and doing what's right for them."
Congress is expected to vote on the resolution later this month.