'Start Here': Democrats sue over Whitaker, Caravan tension in Tijuana and a possible peanut-allergy breakthrough. What you need to know to start your day.

The president said he's finished with his written responses to Robert Mueller.

November 20, 2018, 6:00 AM

It's Tuesday, Nov. 20, 2018. Thanks for choosing to start here.

1. Senate Democrats sue to block Whitaker's appointment

Three Senate Democrats have filed a lawsuit challenging the appointment of Matthew Whitaker as acting attorney general.

Sens. Richard Blumenthal, D-Conn., Sheldon Whitehouse, D-R.I., and Mazie Hirono, D-Hawaii, all of whom sit on the Senate Judiciary Committee, are arguing that because Whitaker was never confirmed by the Senate, President Donald Trump violated the Constitution's Appointments Clause in naming him to oversee the Department of Justice and the Russia investigation.

Whitaker has been openly critical of special counsel Robert Mueller in the past, at one point suggesting the Russia investigation could become a "witch hunt" and saying there had been no collusion between the Trump campaign and Russia. In a recent interview with Fox News' Chris Wallace, Trump said he didn't know Whitaker had criticized the Russia probe, but added he wouldn't stop the acting attorney from limiting its scope.

ABC News White House Correspondent Karen Travers tells us: "If this [investigation] were to continue going on and on and growing, [Whitaker] thinks there should be limitations put on it. He's now in a position where he could put those limitations on it, and as we heard from the president this weekend, he's going to let him do it."

2. 16 House Democrats oppose Pelosi

House Democratic Leader Nancy Pelosi has said she's confident she'll be the next House speaker, but a group of 16 House Democrats have signed onto a letter opposing her bid, calling for "new leadership."

"We are thankful to Leader Pelosi for her years of service to our Country and to our Caucus," the letter reads. "However we also recognize that in this recent election, Democrats ran and won on a message of change."

Behind closed doors, Pelosi is aggressively lobbying House colleagues to attract support. Most Democrats are "playing 'Let's Make a Deal,' Congress-style," ABC News Deputy Political Director MaryAlice Parks tells us. That includes progressives on Capitol Hill who are angling for equal representation on every committee, according to a source.

House Minority Leader Nancy Pelosi, D-Calif., talks to reporters during a news conference at the Capitol, Nov. 15, 2018.
J. Scott Applewhite/AP

3. Tensions high in Tijuana as caravan arrives

There have always been a lot of roadblocks facing the migrants that made their way, mostly by foot, from Central America up through Mexico.

Many assumed the biggest roadblock would be the American government.

But now, many members of that original caravan have now made their way to Tijuana, and ABC News Foreign Editor Kirit Radia tells us that some the people protesting them there are from Mexico.

Central American migrants remain by the U.S.-Mexico border fence in Playas de Tijuana, Mexico, Nov. 15, 2018.
Alfredo Estrella/AFP/Getty Images

4. New peanut-allergy drug shows promise

Yesterday, the world got its first look at a study of a drug that could ease the concerns of parents with children who suffer from nut allergies.

ABC News Chief Medical Correspondent Dr. Jennifer Ashton says while the drug would not cure the allergy, it could cut down on negative effects from accidental exposures.

Other news:

'Big hotels writing short-term rental policy is like big tobacco writing health policy': Airbnb responds to critics, including those at the ReformBnB conference in New York.

'But, because of the culture of the police department, at every turn, either the complaints fell on deaf ears, or inadequate investigations would occur, or they would not include me in the investigation at all': A police officer in Nashville is suing her department over alleged retaliation for reporting she was sexually assaulted by a colleague.

'It is especially senseless when a shooting occurs in a healing space of a hospital': A police officer, an emergency room doctor and a pharmacy resident all were shot to death in Chicago by a suspect who also died in the attack.

'You don't go to jail for lying on TV': The lawyer for a woman involved in the alleged GoFundMe scam including her boyfriend and a homeless veteran said she's actually the one who was duped.

'Your hard pass is restored': CNN's Jim Acosta gets his press pass back, and White House journalists get new guidelines on how to ask questions, how to ask followup questions and how to hand over a microphone.

From our partners at FiveThirtyEight:

One Bad Pawn Move Has Kept The World Chess Championship Deadlocked

Last 'Nightline':

R. Kelly's ex-wife tells story of their marriage: 'People have no idea': Drea Kelly was his principal dancer and choreographer, as well as his wife for 13 years and the mother of his children.

Drea Kelly was his principal dancer and choreographer as well as his wife for 13 years and the mother of his children.
9:29

R. Kelly's ex-wife tells her story of their marriage: 'People have no idea'

Drea Kelly was his principal dancer and choreographer as well as his wife for 13 years and the mother of his children.
ABCNews.com

Long live the queens: Drag's gone mainstream: DragCon shows how drag's influence is reaching all corners of pop culture, from TV and Broadway to blockbuster movies and music.

DragCon shows how drag's influence is reaching all corners of pop culture, from TV and Broadway to blockbuster movies, music and more.
6:08

Long live the queens: drag gone mainstream

DragCon shows how drag's influence is reaching all corners of pop culture, from TV and Broadway to blockbuster movies, music and more.
ABCNews.com

On this day in history:

Nov. 20, 1992 -- Fire breaks out at Windsor Castle.

Fire breaks out at Windsor Castle.
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This day in history: Nov. 20, 1992

Fire breaks out at Windsor Castle.
ABCNews.com

The must-see photo:

An archaeologist cleans up the fresco "Leda e il cigno" (Leda and the swan) discovered in the Regio V archeological area in Pompeii, near Naples, Italy, Nov. 19, 2018. The fresco depicts a story and art subject of Greek mythology, with the Queen of Sparta Leda being impregnated by Zeus (Jupiter in Roman mythology) in the form of a swan. (photo credit: Cesare Abbate/ANSA via AP)

PHOTO: An archaeologist cleans up the fresco "Leda e il cigno" (Leda and the swan) discovered in the Regio V archeological area in Pompeii, near Naples, Italy, Nov. 19, 2018.
An archaeologist cleans up the fresco "Leda e il cigno" (Leda and the swan) discovered in the Regio V archeological area in Pompeii, near Naples, Italy, Nov. 19, 2018. The fresco depicts a story and art subject of Greek mythology, with the Queen of Sparta Leda being impregnated by Zeus J(upiter in Roman mythology) in the form of a swan.
Cesare Abbate/ANSA via AP

For more great photos from around the world click HERE.

Hot on social:

Watch as the president receives this year's White House Christmas tree.

President Trump and first lady Melania Trump welcomed the nearly 20-foot Fraser Fir from North Carolina.
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Trumps receive 2018 White House Christmas tree

President Trump and first lady Melania Trump welcomed the nearly 20-foot Fraser Fir from North Carolina.
ABCNews.com

All right, you're off and running. You can always get the latest news on ABCNews.com and on the ABC News app. Details on how to subscribe to the "Start Here" podcast are below. See you tomorrow!

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