Washington (CNN) A series of legislative and symbolic deadlines come to a head this week in Washington amid a slew of polling that suggests President Donald Trump is historically unpopular at this early moment in his White House.

If there is a turnaround in the offing for Trump, it begins this week.

Let's start with the most pressing piece of business: The government will run out of money and shut down unless some sort of spending bill -- short-term or long-term -- is passed by Friday night. Republicans had insisted privately for some time that there would be no shutdown, understanding that blame for such a move would lie at their feet given that they control all the levers of power in Washington.

But that "don't worry, we'll figure it out" calculus was badly disrupted last week when the Trump administration made clear it wanted $1.4 billion included in the spending bill as a sort of down payment on the President's much-promised border wall.

Homeland Security Secretary John Kelly told CNN's Dana Bash on Sunday that Trump "will be insistent" about the inclusion of funding for the border wall, noting: "I think it goes without saying that the President has been pretty straightforward about his desire and the need for a border wall."

White House chief of staff Reince Priebus and Office of Management and Budget Director Mick Mulvaney refused to say whether Trump would veto a spending bill that didn't have the wall funding included.

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It remains to be seen how hard a line Trump will take as the deadline to fund the government draws near. What is crystal clear is that Trump will get no Democratic votes for a spending bill with funding for a border wall included. And, it's possible he will lose moderates within his party concerned about the message that is sending to voters in their swing districts. Trump could also lose support among conservatives concerned about adding to the deficit.

Then there is the not-quite-dead-yet health care bill, which the White House spent the last week insisting was gaining support and might come up for a vote this week.

"The plan gets better and better and better, and it's gotten really, really good, and a lot of people are liking it a lot," Trump said of the bill last week. The problem is that beyond that happy talk, there's little evidence of any sort of momentum for the legislation, which failed even to garner a vote when House Republicans first tried last month.

The White House appears to be backing away from its initial urgency -- perhaps in recognition of the fact that the votes (still) aren't there for a health care overhaul.

"It's a marathon, not a sprint," Priebus said on "Meet the Press" Sunday. "We're hopeful for this week, but it doesn't have to happen to define our success."

Success is much on the mind of Priebus and his boss as this Saturday marks Trump's 100th day in office. While Trump dismissed the marker as "ridiculous" in a tweet last week, he is clearly focused on wracking up as many wins as possible before Saturday. With that in mind, Trump is set to roll out the broad outlines of a tax reform proposal Wednesday. Trump is also slated to speak at the Holocaust museum Tuesday. He is set to sign a series of executive orders on energy on Friday. And the White House will roll out a website this week designed to highlight Trump's accomplishments over this first 100 days.

On Saturday, Trump will hold a major rally in Harrisburg, Pennsylvania, as a sort of cap of those first 100 days. That rally comes the same night as the White House correspondents' dinner, an annual gathering of politicians and the media in downtown Washington. Trump previously announced that neither he nor his senior staff would be attending the dinner due to the testy relationship between the administration and the media.

Framing all of this are two new national polls that show Trump struggling to win the approval of many Americans. A Washington Post-ABC News poll released Sunday showed 42% approval and 53% disapproval for Trump. That makes Trump the first president in the modern era of polling to have an approval rating under 50% upon nearing 100 days in office. An NBC News-Wall Street Journal poll also released Sunday showed nearly two-thirds of respondents thought Trump was off to a "poor" or "only a fair" start. Thirty-five percent said Trump was off to a "great" or "good" start.

Trump tweeted twice in response to those polls, picking out a silver lining:

New polls out today are very good considering that much of the media is FAKE and almost always negative. Would still beat Hillary in ..... — Donald J. Trump (@realDonaldTrump) April 23, 2017

...popular vote. ABC News/Washington Post Poll (wrong big on election) said almost all stand by their vote on me & 53% said strong leader. — Donald J. Trump (@realDonaldTrump) April 23, 2017

Add it all up and it's clear that this week is a major moment for Trump -- and Washington more generally. Can Trump find a way to rally his party behind a bill to avert a government shutdown and execute a focused run-up to his 100th day? Or will this week be like all those before it: Chaotic and random, driven by a President who seems to change his mind about matters large and small every day?