Axios

A new Quinnipiac University poll puts New York City Mayor Bill de Blasio at the the least favorable among 2020 Democratic candidates while a majority of independent voters said they won't be voting for President Trump in 2020.

By the numbers: De Blasio is polling at 45% unfavorability, followed by Sen. Bernie Sanders (I-Vt.) who is polling at 48% unfavorability. Meanwhile, 54% of independent voters and 10% of Republicans said they will not be voting for Trump.

A classified Internal Revenue Service draft memo obtained by the Washington Post indicates that President Trump's tax returns must be handed over to Congress unless the president invokes executive privilege.

Details: The memo was reportedly penned last fall by a lawyer in the Office of Chief Counsel and is not reflective of the agency's "official position," per the Post. Disclosure to the committee is "mandatory, requiring the Secretary to disclose returns, and return information, requested by the tax-writing Chairs," per the memo titled "Congressional Access to Returns and Return Information."

It was expected that former Vice President Joe Biden would do well with the same big-dollar donors once loyal to President Obama, but 97% of the overall contributions to Biden's presidential campaign came from those who donated less than $200, reports AP.

The big picture: Other 2020 candidates have rejected major fundraisers and boasted about their success with grassroots fundraising. Biden's team is saying these recent numbers illustrate that not only can Biden compete with other Democratic candidates, but also with President Trump's strong campaigning efforts, per AP.

If Congress does not fund the Department of Homeland Security's $1.1 billion funding request, the agency will ask for $232 million from the Transportation Security Administration to be used for the border, NBC News' Julia Ainsley reports.

Why it matters: This would be yet another drastic step taken by DHS to provide more support to border officials struggling to handle the surge of migrants. Already, DHS has started sending hundreds of TSA employees to the border. It has asked the Pentagon to provide migrant housing and begun flying migrants to less crowded processing centers. FEMA has also been asked to contribute part of its budget to border efforts, per NBC.

Go Deeper: On the scene: The Pentagon commits to the border crisis

A lawyer for former White House counsel Don McGahn sent a letter to House Judiciary Chairman Jerry Nadler (D-N.Y.) Monday saying he won't testify before the House committee.

Details: The letter was sent after the Trump administration said it told McGahn to defy a subpoena from the House Judiciary Committee and not testify at a scheduled hearing on Tuesday.

President Trump traveled to Montoursville, Pennsylvania, on Monday night — expressing confidence in his ability to win the key battleground state and taking the opportunity to attack former Vice President Joe Biden.

Details: Just 2 days after Biden hosted his own public event in Pennsylvania, the president campaigned on behalf of Republican Fred Keller, who faces Democrat Marc Friedenberg in a Tuesday election to fill an open House seat. The president frequently uses rallies to deride his opponents, but on Monday directed much of his commentary toward Biden.

In recent years, the accelerating cross-border flow of migrants fleeing violence and poverty has remade the politics of Europe and the United States.

What to watch: A startling new study from Stanford University warns that the conflicts we've seen to date may just be the opening act of a much larger and more dangerous drama.

Kamala Harris wants to use the power of the presidency to close the gender pay gap.

Driving the news: Her new proposal: Use executive action to ensure federal contractors act first, then get Congress to fine big companies 1% of profits for every 1% of pay gap.

U.S. Customs and Border Protection said a 16-year-old Guatemalan boy died on Monday while detained by the Border Patrol in south Texas, AP reports.

The big picture: The migrant youth's death is the 5th incident since December. CBP has already received criticism of its migrant care. The White House requested $4.5 billion in emergency funding last month to help manage what it called a "humanitarian and security crisis."

2020 Democratic candidate Sen. Kamala Harris revealed a proposal Monday to help close the gender pay gap in the U.S. by fining companies with more than 100 employees that don't guarantee equal pay, CNN reports.

Why it matters: Full-time women in the workforce earned 80% of what males earned in equivalent professions while black and Hispanic women earned even less, according to 2017 data from the U.S. Census Bureau.

President Trump plans to formally launch his re-election campaign next month, likely with a burst of swing-state rallies, Republican sources tell me.

Why it matters: Trump's personal campaign approach is aimed at sowing further division in the huge Democratic field and trying to dominate the news so the national discussion hovers on his turf.

A new poll designed to test President Trump’s vulnerabilities on foreign policy heading into the 2020 election finds that economic pain from the China trade war, unraveling alliances and Trump’s relations with Russia are of particular concern to swing voters.

Why it matters: The poll was commissioned by National Security Action, a group founded by former top Obama administration officials that is advising Democratic candidates on foreign policy. Jeff Prescott, the group’s executive director, says that while Republicans and incumbents traditionally have an advantage on national security, that's undercut by concerns over Trump’s temperament. He contends that Democrats have “a real opportunity to go on offense” on foreign policy in 2020.

President Trump told Fox News' "'The Next Revolution with Steve Hilton" he's "very happy" about the trade war with the Chinese — which he said prompted firms to move production out of China and in to other Asian countries.

Because I love the farmer, we are going to be taking in possibly $100 billion, possibly more than that in tariffs."