House Minority Leader Nancy Pelosi of Calif. speaks during a news conference on Capitol Hill on June 4, 2015. (AP Photo/Susan Walsh, File)

House Minority Leader Nancy Pelosi (D-Calif.) is coming to President Obama’s aid by vowing to support and aggressively sell the administration’s nuclear deal with Iran ahead of a vote in September.

Pelosi praised the deal at a news conference on Thursday, calling it the “best possible option” for “stopping the proliferation of weapons of mass destruction” in the Middle East. She also suggested that Republican opponents of the deal had not read it.

As the Post’s Paul Kane reports, every vote will count when the House assembles to consider the deal in mid-September:

If Congress reached a veto-proof majority disapproving of the deal, Obama would be restricted from lifting congressionally mandated sanctions against Iran. Ending those sanctions is the key U.S. offer to Iran in exchange for curtailing its development of a nuclear weapon.

Those votes in the House and Senate are likely to produce majority opposition to Obama’s deal, given the widespread outrage from congressional Republicans since the agreement was announced Tuesday. Whether those opponents can muster large enough majorities to override a presidential veto remains a longshot, however …

Pelosi’s full-throated support, this early, should provide the backing Obama needs as the backstop. If the president and Pelosi can keep more than 145 of the 188 Democrats on their side, they will be able to sustain his veto.