Washington (CNN) Caught flat-footed by the suddenly increasing popularity of the GOP tax plan, leading Democrats are urging the party's candidates to ignore the day-to-day controversies surrounding President Donald Trump's White House and focus their campaigns on the economy.

The scramble to reignite opposition to a tax plan that was deeply unpopular when it passed in December but is now seen favorably by about half of voters comes as Democrats fear that their chances of claiming House and Senate majorities in November's midterm elections are slipping.

Backed by the Koch brothers' network's spending on television ads, Trump and Republicans have aggressively sold the tax plan by highlighting the $1,000 bonuses some businesses have handed out -- contrasting that with House Democratic leader Nancy Pelosi's characterization of the plan as "the crumbs that they are giving to workers to kind of put the schmooze on."

New Mexico's Rep. Ben Ray Luján, the chairman of the Democratic Congressional Campaign Committee, on Wednesday countered Pelosi.

"I recognize that something was in there. And where I come from, anything makes a difference," Luján said.

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