While Warren did not immediately respond to a request for comment from CNBC.com, she has in the past repeatedly said she's not running. Of course, that hasn't stopped candidates in the past from stepping back into the fray.
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But with Democratic front-runner Hillary Clinton—whose all-but-certain candidacy also has not been declared—running a fundraising locomotive and Warren without an organized national effort, the chances appear slim.
If she did get in the race, it would be a headache for Wall Street, which has come under withering criticism from Warren. In that respect at least, a Warren candidacy could benefit Clinton.
Warren's "real goal is to push the party to the left, to move the dialogue toward a more populist anti-Wall Street agenda," Greg Valliere, chief political strategist at Potomac Research Group, told CNBC.com in a phone interview. "She may succeed in doing that. In the process, she will make Hillary look moderate in comparison."
As things stand in the party now, it appears that Vermont Sen. Bernie Sanders, an independent who caucuses with Democrats and is reliably liberal, looks like the only threat to Clinton.
Judging from her organizational efforts, or lack thereof, toward a national campaign, Valliere thinks Warren is probably to be believed when she says she's not running.
"Here we are in early 2015. She would have to begin some initial organizational work if she was going to put together a campaign," he said. "She would have to be at least starting to talk to people about fundraising and staff. There's absolutely no sign of that right now. It's getting a little late in the game, especially going up against a juggernaut like the Hillary Clinton campaign."