Story highlights Their memo comes as GOP senators are poised to approve their tax bill

They say the bill protects interests that are anathema to Trump voters

Washington (CNN) President Donald Trump's tax reform push has handed Democrats a "golden opportunity" to get past the party's internal divisions that have raged since last year's election, Hillary Clinton's and Bernie Sanders' campaign managers argue in a joint memo they're set to release Friday.

Robby Mook and Jeff Weaver say in the memo that the tax effort is "already resoundingly unpopular across just about every demographic," including the rural and suburban voters who flocked to Trump last year and the Democratic base voters who sat out the election.

That has given Democrats a way to avoid having to decide which of those groups to pour money and organizing efforts into winning back in the 2018 midterm elections, they write.

"It is quite a feat for Republicans to have designed a bill that could alienate Obama-Trump voters, Romney-Clinton voters and base Democrats all at the same time, but the tax plan achieves exactly this trifecta," Mook and Weaver write in the memo.

"Should the legislation reach President Trump's desk, the issue has the potential to doom Republican lawmakers who vote for it. If Democrats properly seize this issue, they can potentially win over most every swath of the electorate critical to next year's midterm elections."

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