Updated at 6:20 p.m. ET

Democrats and President Trump are launching an aggressive public relations campaign in hopes of winning popular support as the 18-day partial government shutdown drags on with no resolution in sight.

The two sides hope to sway voters in a pair of nationally televised speeches set to begin at 9 p.m. ET. The goal on both sides is to build an arsenal of public support to try to force an end to the shutdown. They also hope to win a critical political victory in the showdown over Trump’s demand to build a wall on the U.S. border with Mexico.

Top Senate and House Democratic and Republican leaders were invited to a meeting at the White House on Wednesday to discuss the shutdown, according to multiple congressional sources. Trump and Vice President Pence are also set to speak with Senate Republicans on Wednesday.

Trump’s wall has transcended typical Washington bickering over policy goals to become a political battle over the central ideologies of both parties. Democrats insist the wall is immoral, and Trump says it is imperative.

Trump will begin with a speech from the Oval Office on what he describes as a crisis on the border with Mexico. House Speaker Nancy Pelosi, D-Calif., and Senate Minority Leader Chuck Schumer, D-N.Y., will then respond from the Capitol, in part they say to correct the record after Trump speaks.

“Democrats and an increasing number of Republicans in Congress have repeatedly urged the President and Leader McConnell to end the Trump Shutdown and re-open the government while Congress debates the President’s expensive and ineffective wall,” Schumer and Pelosi said in a statement on Tuesday. “Unfortunately, President Trump keeps rejecting the bipartisan House-passed bills.”

Republican congressional leaders have largely backed Trump in his push for the wall. Senate Majority Leader Mitch McConnell, R-Ky., dismissed Democrats Tuesday, blaming them for refusing to budge on the wall.

“Walls and barriers are not immoral. How silly,” McConnell said in a speech on the Senate floor. “It is just political spite.”

But Democrats say the stalemate over Trump’s demand for $5.7 billion to build a wall on the border with Mexico worsened over the weekend after the White House issued an updated list of demands that includes 234 miles of new steel wall.

House Majority Leader Steny Hoyer, D-Md., said a new batch of polling shows voters back Democrats or want a compromise now. He said the White House ignored those statistics when issuing the updated request.

“There was a very negative reaction by the American public,” Hoyer said. “They escalated their demands, not compromised their demands.”

“McConnell has the ability to put these bills on the floor and say to the president of the United States, ‘We’re an independent branch; we’re not the president’s handmaids,’ ” Hoyer added. “We ought to pass bills that we believe are good policy.”

Democrats are also working to sway some moderate and skeptical Republicans to abandon Trump on the wall. Last week, seven House Republicans voted with Democrats on a package of bills to reopen the government without an immediate resolution on the wall. Hoyer said he believes even more Republicans could join them later this week when Democrats begin holding votes on individual spending bills that were written last year by GOP committees.

“These are bills that the Republican Senate passed 92-6,” Hoyer said. “There’s an opportunity for every American to see who wants government open, and our responsibility is not to do what the president of the United States tells us to do.”

Pence and Secretary of Homeland Security Kirstjen Nielsen are expected to counter that argument Tuesday evening when they meet with House GOP members.

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