An internal survey by leading Democratic pollsters shows Hillary Clinton losing working class voters, and the firm is pressing Democrats to rework their messaging as part of a three-pronged plan to create an "electoral earthquake" in November.

"We are witnessing the crash of the Republican Party as we know it, and progressives should dramatically change their strategy to maximize conservative losses and move the stalled progressive reform agenda ahead in the election’s aftermath," according to a memo from the Democracy Corps, a Democratic polling firm run by Clinton allies Stan Greenberg and James Carville.

The memo, written before the withdrawal of Sen. Ted Cruz (R., Tx.) and Ohio Gov. John Kasich from the Republican primary, lays out an election strategy that would capitalize on GOP division in order to deliver not just the White House but also the Senate.

"The fracturing of the Republican Party has created three new short-term opportunities to magnify the probability of an electoral earthquake in November," the memo states.

Democracy Corps identified the three opportunities as capturing moderate Republican votes, turning out young people and single women in large numbers, and broadening Democratic appeal among working-class voters.

The memo offers a more unvarnished take on polling data than an accompanying, publicly-available memo published on Democracy Corps’ website.

While the group publicly recommended that Clinton adjust her messaging, the internal memo, circulated at last month’s meeting of the Democracy Alliance donor club, reveals additional details about its internal data and strategies to employ it.

According to Democracy Corps, Clinton lacks the strength of either presumptive Republican nominee Donald Trump or Democratic rival Bernie Sanders among those working-class voters.

Publicly, the Democracy Corps downplayed that polling.

"The Trump white working-class strategy is faltering because every white working-class man abandoning the Democratic candidate is being erased by Republican losses with the white working-class women," it said in the version of the polling memo on its website.

The private version of the memo, dated ten days after the version on its website, was less sanguine about Clinton’s prospects.

"Hillary Clinton has only reluctantly engaged on economic issues, political reform, and bad trade agreements, and she is losing working class voters in the primary and general, according to our polls," the private memo reveals.

"Progressives will achieve an earthquake election only if they strategize to win the RAE and the big economic argument," it said. The memo recommended substituting more upbeat messaging about expanded economic opportunity with language that attacks the wealthy and corporate America.

Democracy Corps also sees an opportunity to capture moderate Republican votes with Trump at the top of the GOP ticket, a detail that was not explored in the public version of its poll findings.

The group’s internal polling showed that just 60 percent of self-identified GOP moderates would commit to supporting Trump in a contest against Clinton. One out of ten would support the Democratic nominee. The rest would vote for someone else, would not vote at all, or are not sure.

The third opportunity for Democrats lies in turning out what the memo, and the larger progressive movement, calls the Rising American Electorate: young people, single women, and people of color.

"It is even more important to expand the scope of [voter] registration efforts and mobilize infrequent voters, but it is taking place at a moment of rising interest and growing clarity on the stakes," the memo says.

Democracy Corps predicts that those strategies, in conjunction with a "three-front GOP civil war" between Trump supporters, conservatives, and moderates, will produce not just electoral gains but policy victories.

The group predicted that Democrats would win not just the presidency but the Senate as well. Republicans would likely hold "a small majority in the House," it predicted, that would enable Democrats to force through major policy items.

"The civil war will only grow more intense in the [election’s] aftermath, and some GOP leaders and elected officials will support policies unthinkable only a short time ago," the memo predicts.

Though it is aligned with Democrats, Democracy Corps is a 501(c)(4) "dark money" nonprofit, and therefore cannot directly collaborate with political campaigns.

However, the group has close ties to Greenberg’s polling firm, which it paid more than $650,000 in 2013, according to its most recent annual tax filing. Democratic candidates, political groups, and party organs have paid Greenberg’s firm nearly $880,000 so far this cycle.