More specifically: The GOP-passed tax plan that led companies to announce bonuses that House Democratic leader Nancy Pelosi dismissed as "crumbs" compared with "the bonus that corporate America received" may be popular enough that it can lessen the danger of Republicans being wiped out by a blue wave in this year's midterm elections.

Near Cincinnati on Monday, President Donald Trump compared Pelosi's "crumbs" comment to Hillary Clinton referring to half of Trump's supporters as belonging in a "basket of deplorables" during the 2016 presidential election.

"Nancy Pelosi again said that's 'crumbs,' " Trump said. "Well, she's a rich woman who lives in a big, beautiful house in California, who wants to give all of your money away."

Trump was celebrating what could be a sudden change of political fortune for Republicans who for months have worried that their House majority is in jeopardy in November.

A Quinnipiac University poll out Wednesday pegged Trump's approval rating at 40% -- matching recent CNN and Gallup polls to deliver his best rating in seven months. A slim majority of voters, 51%, say they approve of how Trump is handling the economy -- and they now say that Trump, not former President Barack Obama, is primarily responsible for the economy's health.

The GOP-passed tax bill's approval rating jumped from 26% at its passage in late December to 39% -- not nearly as high as Republicans would like to see, but a stark improvement over what once looked like a political albatross.

And Democrats now hold a 9-point edge in a generic congressional ballot -- where voters are asked, simply, whether they prefer a Democratic or Republican representative. Weeks ago, pollsters had pegged the Democrats' edge in the mid-teens.

At the same time, Democrats this week won a Missouri state House special election in a district that Trump had won by 28 points in November 2016.

"We don't have the majority in the bag -- nor should we have our head in a bag hyperventilating," said Jesse Ferguson, a Democratic strategist who directed the House Democratic campaign arm's spending on individual races in 2014.

Tax bill fuels resurgence

Republican strategists credit the tax plan's passage with their suddenly rosier prospects in this year's midterms.

They expected a brawl with Democrats over the benefits the plan delivered to large corporations. And they knew they'd need to claim credit for changes to some workers' paychecks, which Republican groups are attempting to do with TV ads in key House districts.

But the business community's response -- with some companies announcing bonuses for their workers and others crediting the tax bill with plans to expand or move money back into the United States -- is the real driver of the shift in public opinion, several strategists said.

"I don't think Democrats anticipated the business response," one GOP strategist involved in 2018 races said.

"There's a daily announcement of a company investing more money in their employees, investing in the economy," the strategist said. "They weren't expecting that response."

Many GOP operatives were never convinced they were as far behind as previous polls showed in the generic congressional ballot -- and some urged caution now, even as they acknowledged the party had rebounded.

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Can it last?

There are plenty of reasons to believe the Republican resurgence could be short-lived: The stock market plunged on Friday and Monday. And Democratic challengers outraised their Republican House incumbents in nearly three dozen districts in 2017's final quarter.

"There are still some question marks here as to where this thing is going to go," said Brandon Scholz, a Republican strategist in Wisconsin, which features competitive Senate and governor's races next fall.

He pointed to the GOP's loss of a state Senate special election there last month in a district Trump had carried by 16 percentage points in 2016.

"Republicans had the right playbook, they had the right candidate, everything was right; they just didn't see these Republican (voters) staying at home," he said.

Questions around Trump -- including the Russia investigation and the President's willingness to stick to the message the GOP wants to see him drive -- loom large every day.

"The fundamentals have not changed that Trump is unpopular, his agenda is not liked and Democrats are fired up to take control of Washington away from him," Ferguson said. "The one (thing) that keeps me up at night is the torrential downpour of cash that Republicans are going to get now that they passed the tax bill, and making sure that while Democrats aren't going to be able to match that, we need to at least meet them on that field of battle and fight back."

The politics around the tax bill also remain far from certain: House Speaker Paul Ryan over the weekend was assailed for a tweet -- since deleted -- that pointed to the extra $1.50 per week a high school secretary was receiving as a result of the tax plan's passage.

"As the Dow nosedives on his watch, the President's rambling, deceitful tax scam sales pitch reached an all-time low in Cincinnati," Pelosi spokesman Drew Hammill said.

"While Speaker Ryan touts a $1.50 a week tax cut for the middle class, President Trump is desperately seeking to hide the multi-billion dollar corporate windfalls of the GOP tax scam behind meager, one-time bonuses," Hammill added.