The Democrats noted that Texas is home to roughly 1,200 miles of the U.S.-Mexico border — much of it private property that could be seized to build Trump's promised barrier that he claims is necessary to prevent illegal immigration and crime.

ADVERTISEMENT "We believe that it would be the largest federal land grab of Texas land in history."

The Senate is poised to vote Thursday on a House-passed resolution, sponsored by Castro, that would block Trump's emergency declaration at the southwest border.

The resolution is deemed "privileged," meaning it's guaranteed a vote in the GOP-led Senate, despite opposition from many Republicans in the upper chamber.

"This land grab is massive, it's un-American, it's un-Texan, and it continues to ignore the real issues that we're living with on the border," said Rep. Vicente Gonzalez (D-Texas), who represents a border district.

Many of the recent migrants have come to the southern border from Central America, where violence and corruption are rampant. Gonzalez is calling for more aid to the troubled region, to provide "economic investment that will encourage the citizens of those countries to want to stay home."

"That would be getting to the root of the problem," he said.

“After years of uncertainty, Texas families who live and own land along the Red River can rest easy that the federal government has no rightful claim to their property,” Cornyn said in a statement

Escobar is asking that he apply the same protections to landowners along the border.

"He's talking about protecting private property, American property owners, in North Texas," she said. "We would ask that he have the same enthusiasm for protecting the ... private property rights of his constituents in South Texas, as well."

Trump has sought to use his order, issued last month, to shift billions of dollars that Congress had previously approved for other programs — including $3.6 billion for military construction projects — to expand the border wall he'd promised during the 2016 campaign.

The declaration came after Congress rejected $5.7 billion Trump had demanded for new wall construction as part of an enormous government spending package passed by both chambers in February. GOP leaders had pressed Trump to sign the bill to prevent another government shutdown. Trump did so, but only reluctantly, since it excluded the wall funding. The emergency declaration was the president's strategy for side-stepping Congress to secure that money.

Democrats, joined by a handful of Republicans, are fighting back, characterizing the emergency declaration as an executive power grab that violates the Constitution's separation of powers and defies Congress's unique authority to dictate where taxpayer dollars are spent.

Trump has promised "100 percent" to veto the measure.

"Any rational, reasonable judge out there is going to see that this is not an emergency," said Rep. Henry Cuellar (Texas), yet another border Democrat. "Those of us who live on the border, we certainly know that there's no emergency down there."

The Texas Democrats are also pointing to the potential loss of federal dollars if military construction funding is shifted to underwrite the border wall. The Pentagon has not identified which projects would be specifically affected, but Texas is home to a number of huge military installations, including Fort Bliss and Joint Base San Antonio.

Cuellar estimated the losses to the state could be $520 million.

Cornyn and Cruz "should be supporting our troops," said Escobar, "not supporting President Trump's campaign commitments."