The Senate's top Democrat on Sunday announced his support for the Iran nuclear deal, further strengthening President Obama's effort to overcome opposition to the agreement in the Congress, and even raising the chance that Democrats could filibuster a GOP plan to disapprove of the deal.

"I strongly support this historic agreement and will do everything in my power to ensure that it stands," said Sen. Harry Reid (D-NV) in a written statement.

ajc.com

Credit: Jamie Dupree

icon to expand image

Credit: Jamie Dupree

After staying on the sidelines for several weeks, Reid issued his statement on the Iran nuclear deal just a day before President Obama was slated to visit Reid's home state of Nevada.

"At the end of the day, there is no doubt in my mind that the threat of Iran gaining a nuclear weapon – the one outcome we all agree is unacceptable – is far more likely if Congress rejects this agreement," said Sen. Harry Reid (D-NV).

So far, only two Democrats in the Senate have announced their opposition to the Iran deal - Sen. Charles Schumer (D-NY) and Sen. Robert Menendez (D-NJ).

Maybe no need for a veto?

With most Democrats sticking with the President so far on the Iran deal, it is conceivable that Mr. Obama might not have to even veto a resolution to disapprove of the deal.

Why? If enough Democrats stand with the President, they could filibuster the resolution in the Senate, and not even allow a final vote.

Democrats currently control 46 seats; they could afford to lose five votes, and still be able to filibuster the "resolution of disapproval" on the Iran agreement.

A number of Democrats remain undecided at this point, but the trajectory has been very obvious in the two weeks that President Obama was on vacation in Martha's Vineyard, as Democratic leaders issued statements on almost a daily basis about lawmakers announcing they would support the agreement.

Liberal groups are exerting pressure on those undecided Democrats, trying to keep them behind the President on the Iran deal.

"Join us in pledging to withhold contributions from Democrats who sabotage diplomacy with Iran," read a fundraising email sent out by MoveOn dot Org over the weekend, using Ben and Jerry, the co-founders of Ben & Jerry's Ice Cream to make their pitch.

"We're writing today about keeping America out of another war in the Middle East," the email read.