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President Trump used an address Monday to the American Farm Bureau convention to dig in on his call for a border wall, even as new polling indicates most Americans oppose his administration’s strategy of demanding money for the U.S.-Mexico barrier in exchange for ending the partial government shutdown.

Speaking in New Orleans, Trump said there was “no substitute” for a physical barrier along the southern border with Mexico and accused Democrats of playing politics in refusing to negotiate on the issue.

“They think if they stop me, it’ll be good for 2020,” Trump said of Democrats in Congress. “We need that barrier. … If you don’t have that barrier there, there is not a thing you can do.”

LONGEST-EVER GOVERNMENT SHUTDOWN SEES NO END - AND NO COMPROMISE - IN SIGHT

But as the partial shutdown enters its fourth week and hundreds of thousands of federal workers miss their first paychecks, fresh polling suggests the president is losing the battle of public opinion.

A Quinnipiac University poll released Monday found that 63 percent of voters agree with the Democratic proposal to reopen parts of the government that do not involve border security, with 30 percent opposed. The same poll found 63 percent also oppose using the shutdown to force wall funding, with just 32 percent supporting.

The poll found that 56 percent of American voters blame Trump and Republicans in Congress for the partial shutdown, compared with 36 percent who say Democrats are responsible.

An earlier Washington Post-ABC News poll also found more Americans blame Trump and the Republicans than the Democrats over the stalemate -- though the same survey showed support for a wall growing to 42 percent, up from 34 percent a year ago.

Yet neither side is showing any sign of budging, with Trump continuing to insist on upwards of nearly $6 billion for a border wall and Democratic congressional leaders saying they will not entertain a wall in this funding package.

Senate Minority Leader Chuck Schumer, D-N.Y., hit back at Trump on Twitter – telling the president that if he wants to help farmers, he should re-open shuttered agencies.

“President [Trump] is speaking to farmers in Louisiana,” Schumer tweeted. “But [the U.S, Department of Agriculture] can’t pay out promised aid during the #TrumpShutdown. They can’t implement the new provisions in the Farm Bill. Farmers can’t get loans."

Schumer added: “Mr. President: If you want to help farmers, re-open the government.”

During his speech, however, Trump said that a border wall and stricter immigration controls would help farmers, while stemming crime and illegal immigration. The president added that he understands that farmers need people to help with harvests and that he'll make it easier for immigrants to enter the country to work on farms.

“When we have proper security, people won’t come, unless they’re the people we want to come,” he said. “You need people to help you on your farms.”

As the partial government shutdown rolled into its 24th day, little headway seems to have been made in the stalemate between the White House and congressional Democrats.

Leaving the White House for his trip to Lousiana, Trump told reporters that he had dismissed a proposal from Sen. Lindsey Graham, R-S.C., to reopen for several weeks and continue dealing with Democrats over Trump's long-promised wall on the U.S.-Mexico border.

"I did reject it, yes," Trump said. "I'm not interested. I want to get it solved. I don't want to just delay it."

TRUMP SAYS VISITING CLEMSON TEAM WITH EAST FAST FOOD 

Trump also backed further away from the idea of declaring a national emergency as an escape hatch, saying: "I'm not looking to call a national emergency. This is so simple, we shouldn't have to."

Trump has demanded $5.7 billion for his long-promised wall, while Democrats, who oppose the wall as both immoral and wasteful, insist Trump re-open the government before they negotiate border security.

Democrats oppose an emergency declaration but may be powerless to block it if Trump goes that route. Some Republicans are wary, too, fearing how a future Democratic president might use that authority. Such a move would almost certainly be challenged in the courts.

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Sen. Chris Coons, D-Del., called Graham's idea to reopen the government a "great place to start."

"I do think if we reopen the government, if the president ends this shutdown crisis, we have folks who can negotiate a responsible, modern investment in technology that will actually make us safer," Coons said.

Trump, during his speech in Louisiana, said he also supported the use of drones and other technology to patrol the border, but added that there is no substitute for a wall.

The Associated Press contributed to this report.