Run Warren Run, an organization created by Democracy for America and MoveOn.org to draft Massachusetts Sen. Elizabeth Warren into the 2016 Democratic presidential contest, has suspended its campaign.

"Today we announce the suspension of our campaign to draft Elizabeth Warren," Move On's Ilya Sherman and Democracy for America's Charles Chamberlain said in a joint commentary published in Politico. "There's no sugar-coating to it. We didn't achieve our central goal. But there's a bigger story that gives us tremendous hope: as one headline put it: Elizabeth Warren may not be running, but she's in the race anyway."

The campaign's final act will be delivering 365,000 "Run Warren Run" petition signatures to Warren's Capitol Hill office. Their effort began early this year, when it appeared that Hillary Clinton would be the unchallenged 2016 Democratic nominee.

MoveON and DFA went all in for Warren and raised donations from their millions of members. Even though Warren repeatedly said that she was not running, the two groups hoped that she would change her mind. To try to pressure Warren, they created the first major on-the-ground campaign operation in Iowa, which revealed a hunger among Democrats for a progressive candidate. Their efforts helped draw more media attention to Warren's statements in the U.S. Senate, where she opposed recent GOP efforts to loosen Wall Street oversight and the Obama White House's continuining push for the Trans Pacific Trade partnership.

Warren's rhetoric that the system is "rigged" has also been adopted by other Democratic presidential candidates, most notably Hillary Clinton, who also has made economic inequality a centerpiece of her domestic agenda. Former Maryland Gov. Martin O'Malley also struck these same notes when announcing his candidacy this past weekend. Vermont Sen. Bernard Sanders has talked about economic inequities for years, but he does not quite have the personal touch that Warren does.

Both MoveOn and DFA were forced to suspend their effort by Warren's refusal to enter the race, they said in a joint statement.

"Running for president is at once an utterly public decision and a deeply personal one. Senator Warren has heard our case, and she declined to run," they said. "We respect her decision. If she chooses to reconsider, due to shifting circumstances or a new intuition, the movement that urged her to run could regroup at a moment’s notice."

Run Warren Run spent $1.25 million trying to persuade her. They opened three offices, nine staffers and five organizers. Another pro-Warren group, Ready for Warren, says they will continue their efforts.