Sen. Elizabeth Warren, D-Mass. speaks on Capitol Hill in Washington. More than 300 former campaign staffers and organizers for President Barack Obama have signed on to a letter urging Warren to run for president in 2016. (J. Scott Applewhite/AP)

After Elizabeth Warren and Ted Cruz attacked the 2015 spending agreement in the Senate last week from opposite ends of the political spectrum, Washington engaged in a little parlor game: Is Warren the Cruz of the left?

Though there are superficial similarities between the Massachusetts Democrat and the Texas Republican, the question is actually easy to answer. Elizabeth Warren is not Ted Cruz. She cannot possibly be Ted Cruz — because she is Jim DeMint.

DeMint, the former Republican senator from South Carolina who now runs the conservative Heritage Foundation, is widely seen as the godfather of the tea-party movement. His fiery rebellions, first against the impure conservatism of President George W. Bush and then more forcefully against President Obama, turned him into a kingmaker among conservatives and the closest thing the tea party had to an ideological leader.

Warren, the populist former Harvard professor, now finds herself in a position very much like DeMint’s in 2006 after the Republicans’ midterm wipeout. After the Democrats’ 2014 midterm debacle, we are seeing the early signs of a left-wing analogue to the tea party emerging, and Warren is well positioned to be its godmother.

Progressives are increasingly disenchanted with the compromises of Obama — just as conservatives had come to see Bush as a turncoat in his second term. Many progressives fear the Democratic Party will nominate Hillary Clinton, who is close to Wall Street and has hawkish foreign-policy views — just as conservatives were wary of John McCain in 2008. If Clinton loses to a Republican in 2016, the liberal anger could explode into an equivalent of what the tea party was in 2009 and 2010 — and Democrats could be purged in primaries for being inadequately doctrinaire.

The left’s tea-party equivalent is still in its infancy. But it could be seen recently in the opposition by environmental activists to the reelection of Sen. Mary Landrieu (D-La.), who lost her seat this month. They wanted to punish her for opposing them on energy issues — even though the conservative replacing her is less to their liking.

This was very much the logic of DeMint, who said he’d prefer a minority of conservative senators to a majority of moderates: “I’d rather have 30 Marco Rubios than 60 Arlen Specters.”

There have long been populist strains on both the left and the right, and though Warren is a social liberal and DeMint a religious conservative, she is channeling the same anti-establishment anger he voiced. She’s just directing it at big corporations instead of big government.

Her “enough is enough” speech on the Senate floor last week went viral among progressives who share her anger at big banks. “Enough is enough with Wall Street insiders getting key position after key position and the kind of cronyism we have seen in the executive branch,” she said. “Enough is enough with Citigroup passing 11th-hour deregulatory provisions that nobody takes ownership over but that everybody comes to regret.”

Her grievances were as much with fellow Democrats as with Republicans. She was furious that banking lobbyists had succeeded in inserting a provision in the spending compromise — negotiated by Senate Democratic leader Harry Reid and endorsed by Obama — undoing a key part of the Dodd-Frank financial regulations. And she’s opposing Obama’s nomination of Antonio Weiss, an investment banker, to the No. 3 position at the Treasury Department.

This is much more like DeMint circa 2006 than Cruz in 2014. Cruz, long an establishment man, arrived late in the tea party movement, opportunistically embracing its themes to vault himself to power in 2012. His stands in Washington have been less about advancing a policy agenda than about causing mayhem and positioning himself to run for the Republican presidential nomination in 2016.

DeMint, by contrast, cared about policy and took a long view of politics. As a member of the House, he pushed back in 2003 against the Bush administration’s Medicare expansion. He fought Republican leaders in the Senate to get rid of earmarks in spending bills, and eventually prevailed. He established a Senate Conservatives Fund and was instrumental in getting colleagues such as Rubio (R-Fla.) and Rand Paul (R-Ky.) elected.

DeMint briefly considered a presidential run in 2011 after conservative leaders tried to draft him, but he decided against it within days; the next year he quit the Senate to run Heritage. Now, hundreds of former Obama campaign workers are urging Warren to run for president — and, though not formally ruling out a run, she has expressed no interest.

I believe her. By all indications, Warren is less interested in running for office than in leading a movement.

Twitter: @Milbank

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