(CNN) Early warning signs are flashing for President Donald Trump on some of his core arguments on immigration, the economy and North Korea that are central to his 2020 re-election message.

Complications on each of those policy areas threaten to undermine the narrative of unprecedented success that the President has weaved around his first two years in office and are driving political debate as the administration unveils its budget on Monday.

A poorer than expected monthly jobs report Friday fed concern that strong economic growth that anchors Trump's best argument for a second term is ebbing -- something that should worry the President since it's a critical reelection metric.

Trump has often claimed that he is presiding over the " greatest economy in the history of our country." But his foundational political promise to eliminate the US trade deficit suffered a blow with new figures showing that the gap between imports and the amount of goods and services that the US sells abroad has grown $100 billion since Trump took office, despite two years of his "America First" tariff policies intended to reinvigorate American manufacturing.

Signs that North Korea could be preparing a missile or satellite launch and its continued expansion of an atomic arsenal undercut the President's claims that his daring outreach to the isolated state has ended its nuclear threat.

And a rise in crossings across the southern border — while playing into Trump's claims of a crisis in the short term, contradict his wider argument that hardline enforcement policies are the best way to manage immigration and suggest his totemic political plan for a border wall may be ignoring the real problem.

Trump appears sensitive to the weak points of his political pitch, and spent the weekend tweeting out glowing testimonials about the economy from allies and accusing journalists of distorting the successes of his presidency.

"Despite the most hostile and corrupt media in the history of American politics, the Trump Administration has accomplished more in its first two years than any other Administration. Judges, biggest Tax & Regulation Cuts, V.A. Choice, Best Economy, Lowest Unemployment & much more!" Trump wrote.

"More people are working today in the United States, 158,000,000, than at any time in our Country's history. That is a Big Deal!"

The good news for Trump is that the election — though it seems increasingly to be on his mind — is 20 months away, and none of the emerging complications are certain to cement themselves in the unpredictable political period ahead. And at their root, presidential elections unfold as a clash between two competing political visions and personalities as much as a contest between rival policy platforms. One of the big questions of the Democratic presidential race is how the eventual nominee will handle the President's willingness to embrace scorched earth campaigning.

Yet the challenges to Trump's re-election message are not happening in a vacuum. He has plenty of other looming political problems as well as he faces an unprecedented multi-front battle with House Democrats who have launched investigations into almost every aspect of Trump's life, political career and business.

The pros and cons of solidifying the base

The way Trump has positioned his presidency — premising his political viability on the fervent support of his base -- means he is insulated to some extent from reversals of fortune. But an eroding re-election argument could also threaten his efforts to win back more moderate voters in swing districts who helped Democrats win the midterm elections last year.

Potential road bumps for Trump's re-election message also help to explain the relish with which Republicans have seized on the growing pains of the new House Democratic majority — giving a glimpse of the searing attacks that will complement the 2020 narrative of Trump success. Many Republican strategists believe that a perceived race to the left by Democrats could give the GOP the best chance of keeping the White House in 2020.

That argument was exemplified by Wyoming Rep. Liz Cheney, the chair of the House Republican conference, on NBC's "Meet the Press" on Sunday.

"They've become the party of anti-Semitism, the party of infanticide, the party of socialism. They've passed legislation that's violated the First Amendment, the Second Amendment," Cheney said.

"It's really time for the Democrats -- the leadership in that party to stop it, to stand up and to act worthy, frankly, of the trust the American people have placed in them."

All first term presidents face the conundrum of how to reconcile the expansive promises they made to win office with an accounting of their wins and losses that comes with the quest to keep their jobs.

More Presidents than not have made that leap in the modern era and won the historical validation of a second term. But few candidates made such extravagant claims to win the Oval Office in the first place as Trump did in 2016.

If today's warning signs turn into significant reversals for the President, Republican plans to run in 2020 on a "Peace and Prosperity" message will be compromised. That could lead the President to put the inflammatory rhetoric that he used in the 2018 midterms at the center of his reelection bid.

Economic numbers cause concern

Any one bad jobs report could be an anomaly. And the economy is largely healthy following a strong run since the Great Recession more than a decade or so across the Obama and Trump presidencies and wages have recently been rising at last.

But any sign that the economic engine has peaked could be spell bad news for a President running for reelection, even if any slowing of the pace is relative.

Figures released by the Census Bureau last week showed the trade deficit at a 10-year high in 2018, up $69 billion.

The jump came despite Trump's crusade to revive American manufacturing and reduce dependence on imports which formed a crucial part of his winning 2016 election message. The data put even more pressure on the President to extract a victory from trade talks with China that are currently believed to be in the final stages - though Beijing has in recent days signaled that there's no rush to hold a signing summit at Trump's Mar-a-Lago resort in Florida by the end of this month, as the President himself suggested.

The White House's own budget estimates are far more rosy than those of independent forecasters. In Trump's new budget to be unveiled on Monday, the administration predicts 3.2% annual growth his year, 3.1% growth in 2020, and 3% GDP expansion the following year, the Wall Street Journal reported.

Trump's failure to reach a deal with North Korean leader Kim Jong Un at their second summit in Vietnam last month dealt a blow to the President's most important foreign policy venture. The White House has rejected criticism of the lack of progress at the two meetings by arguing that the halt to North Korean nuclear and missile tests has been an important victory in itself.

But warnings by analysts based on satellite images that Pyongyang could be preparing to launch a missile or space rocket soon, threatened to undermine even that narrative of limited success.

Trump said last week that he would be "very disappointed if that were happening," while stressing the report was very early assessment.

The restoration work at the launch site could be just a negotiating ploy by Kim after the failure of the summit and just the latest round of decades-long brinkmanship by the North Koreans. But it does show the perils in investing so much political and electoral capital in a diplomatic initiative with the unpredictable North Koreans.

There are also challenges looming for Trump on another signature issue -- immigration.

Customs and Border Protection warned last week that more than 76,000 people were caught crossing the southern border illegally or without proper papers in February -- the highest such number for any February in the last 12 years.

The administration used the figures to argue that the immigration crisis that Trump has proclaimed in an effort to win support for his border wall is getting worse. But critics argue that his fixation on a wall misses the point that the real problem is in a system overwhelmed by asylum claims made at ports of entry.

Trump, however, signaled that his border wall will be a pillar of his political strategy going forward, despite his failure to wring funding for the barrier out of Congress -- an impasse that prompted him to declare a national emergency on immigration.

The White House will ask Congress for $8.6 billion for the wall in the new budget, sources told CNN, prompting a quick response from Democrats at the start of a new showdown over immigration, following last year's government shutdown drama.

"Congress refused to fund his wall and he was forced to admit defeat and reopen the government. The same thing will repeat itself if he tries this again. We hope he learned his lesson," House Speaker Nancy Pelosi and Democratic Senate minority leader Chuck Schumer said in a joint statement Sunday.