WASHINGTON — House Democrats are prepared to support increased spending on border security, but not a wall, if President Donald Trump agrees to reopen the government first, lawmakers and aides said Wednesday.

The proposal, which Democrats are drafting into a formal letter to Trump, will include border security improvements such as retrofitting ports of entry, new sensors and drones, more immigration judges and border patrol agents, and additional technology, among other measures.

The letter was not final and the exact figure Democrats will suggest was not yet determined, but lawmakers and aides said it would be higher than the levels Democrats have supported in the past, which have ranged from $1.3 billion to $1.6 billion.

"We are going to be talking about substantial sums of additional moneys to be invested to secure the borders," said House Majority Leader Steny Hoyer, D-Md. "And it will be a substantial figure."

Some Democrats suggested they would even be willing to meet Trump's request for $5.7 billion — as long as it goes for technology and other improvements, not the physical wall the president is seeking.

"If you look at all of the things that we're proposing - more judges, more border patrol, this new technology - these are the kinds of things that we are gong to be putting forward, and I think that they can be done using the figure that the president has put on the table," House Majority Whip James Clyburn, D-S.C., told reporters Wednesday.

"If his $5.7 billion is about border security, then we see ourselves fulfilling that request, only doing it through what I like to call using a 'smart wall,' " Clyburn said.

The development indicated a new desire on the part of House Democrats to discuss the types of border security measures they support, instead of just standing in opposition to Trump's wall. It comes on Day 33 of the partial government shutdown as Trump and congressional Democrats remain at loggerheads over his demand for $5.7 billion to build more than 200 miles of new walls along the U.S.-Mexico border.

The House has been passing bills all month that would reopen the government without funding the wall, and Democrats plan to do so again later this week. Some members reported pleas for help from constituents who've been hurt by the shutdown.

"I had a farmer who is eligible for those extra credits that the president was offering for farmers hurt by his trade policy, she can't get those extra credits because [the Agriculture Department] is shut down," said Rep. Mary Gay Scanlon, D-Penn. "And the Democrats are totally for border security but we need to have a real conversation about it so let's get the government open and then talk border security."

Still, the House Democratic caucus has largely remained unified behind Speaker Nancy Pelosi, D-Calif., throughout the shutdown, although there have been isolated expressions of anxiety about Pelosi's strategy of refusing to negotiate until the government is reopened.

Speaking on KFGO radio in Fargo, North Dakota, on Tuesday, moderate Rep. Collin Peterson, D-Minn., said that Democrats should "Give Trump the money" and bring the shutdown to an end.

"Why are we fighting over this? We're going to build that wall anyway, at some time," Peterson said, adding: "When I bring up what I have to say (to Democrats), they look at me cross-eyed."

Peterson's view was a distinct minority, with other House Democrats agreeing the government needed to reopen before further negotiations could take place.

In a closed-door caucus meeting Wednesday morning, Pelosi renewed calls for unity in her ranks, citing polling showing Democrats winning the public relations fight around the shutdown, according to a Democratic aide present who spoke on the condition of anonymity to describe the private discussion.

"Understand the impact of the unity of our caucus," Pelosi told her members, according to this aide. She then spoke about how Democrats had defeated former president George W. Bush's attempt to partially privatize the Social Security system by sticking together.

"But understand, there is a plan. It is working for us. I appreciate the unease because we all do," Pelosi said, according to the aide. "It's not just the lives of these workers, which would be reason enough, it's the contractors who are left out in the cold and it's the American people who are not receiving the services that they deserve."

Pelosi also told members not to make plans for their families to travel to the Capitol for Trump's Jan. 29 State of the Union, an address she has suggested the president delay until the shutdown is over, citing security concerns.

"Why does your family want to come to this thing in the first place?" Pelosi remarked, according to the aide.

Trump responded to Pelosi's suggestion with a letter Wednesday saying he'd been assured there were no security concerns and planned to appear in the House Chamber to deliver the address as planned. "It would be so very sad for our country if the State of the Union were not delivered on time, on schedule, and very importantly, on location!" Trump wrote.

However, the House and Senate both have to pass a resolution to allow Trump to deliver the address from the House chamber, which they've yet to do.

There was also new action in the Senate, where Majority Leader Mitch McConnell, R-Ky., set up competing votes for Thursday to end the shutdown.

One is on a proposal from Trump to reopen the government while spending $5.7 billion on the wall that Trump repeatedly said would be paid for by Mexico. The bill would also make additional changes to the immigration system, including new restrictions on the asylum program and temporary deportation relief to certain unauthorized immigrants including the so-called "dreamers" brought illegally to the country as kids.

The other scheduled vote is on a Democratic measure to reopen the government through Feb. 8 without funding the wall, a stopgap measure to open the government during border security negotiations.

Neither measure is expected to get the 60 votes needed to overcome a filibuster.

White House spokeswoman Sarah Sanders said on Fox News Channel that Democrats should support the Trump proposal.

"The plan includes things that Democrats have specifically said they wanted to see, things that we know they want. It's outrageous that they wouldn't support a plan that does all of the things that they claim to want," Sanders said.

"Democrats have got to stop playing politics. Nancy Pelosi has got to start putting the American people ahead of partisan politics."

Shortly before the shutdown began, the full Senate passed a bill like the one Democrats will push Thursday to reopen the government for a short period without funding the wall. But amid conservative backlash Trump turned against it, resulting in the shutdown that began Dec. 22 and has become the longest in U.S. history.

"Let me be very clear. These two votes are not equivalent votes," Senate Minority Leader Chuck Schumer, D-N.Y., said on the Senate floor, speaking about the votes that will take place Thursday. "It's not on the one hand, on the other hand. The president's proposal demands a wall and radical legal immigration changes in exchange for opening up the government. The second vote demands nothing in exchange for opening up the government."

McConnell disputed Schumer's remarks, calling his stance "downright silly."

"The president's compromise offer should command serious consideration in both houses of Congress," McConnell said. "It's hard to think of a good reason to oppose this but my Democratic friends are trying to come up with something, anything, to prolong the stalemate."

Concerns about the toll the shutdown is taking on the federal workforce, important services provided by agencies like the Food and Drug Administration, Transportation Security Administration and Internal Revenue Service - as well as on the economy itself -- have compounded daily. Union members were holding protests around the Capitol Wednesday and planned to march to McConnell's office and hold a sit-in until they get arrested.

On Wednesday the White House's top economist said the economy could completely stall in the first three months of 2019 if the government shutdown does not end.

The comments by White House Council of Economic Advisers Chairman Kevin Hassett, in a CNN interview, represented the most dire forecast yet from a Trump administration official on the shutdown economic's toll, and marked a sharp contrast with the rosy economic news frequently ballyhooed by the president himself.

Hassett was asked if the economy's growth rate for the first quarter of the year could fall to 0 percent if policymakers don't step in soon.

"Yes, we could" see that, he said. "If it extended for the whole quarter, and given the fact that the first quarter [growth rate] tends to be low because of residual seasonality, then you could end up with a number very close to zero in the first quarter."


The Washington Post's Damian Paletta and Rhonda Colvin contributed to this report.