Brown people caravaning into the country. Transgender people using the bathroom. Black people kneeling during the national anthem.

President Donald Trump wants voters to be terrified when they go to the polls on Nov. 6. The theme of the final weeks of the 2018 campaign is that Americans have everything to fear but fear itself. Fear itself, the White House figures, is just savvy politics. It is, after all, how Trump himself was elected.

The suspicious packages with “potential explosive devices” that shook the country Wednesday provided a dark, sobering and fitting backdrop to the election landscape. The packages were addressed to former President Barack Obama, Bill and Hillary Clinton, former CIA Director John Brennan, former Attorney General Eric Holder and Rep. Maxine Waters (D-Calif.); a similar package had been sent to Democratic donor George Soros earlier in the week. All of these individuals have been criticized by Trump.

There is no suspect or motive at this time.

Democrats have made preserving access to health care their central message in the campaign. For the first time since the Affordable Care Act passed nearly a decade ago, Republicans are on the defense on this issue. And the tax law, which was supposed to be their signature legislative accomplishment, has proven to be unpopular.

“Desperate House Republicans therefore have no positive issues to campaign on, and are resorting to gross fear mongering and dog whistle politics,” said Tyler Law, spokesman for the Democratic House Campaign Committee.

Instead, in recent days, Trump has ramped up his immigration attacks. His foil is a group of mostly Central American migrants heading toward the United States. The so-called “caravan” has swelled to more than 6,500 members who have joined to find safety in numbers and to draw attention to their plight.

Trump has portrayed these migrants as terrorists and criminals who would threaten the safety of the country’s citizens if the entered the United States.

I am watching the Democrat Party led (because they want Open Borders and existing weak laws) assault on our country by Guatemala, Honduras and El Salvador, whose leaders are doing little to stop this large flow of people, INCLUDING MANY CRIMINALS, from entering Mexico to U.S..... — Donald J. Trump (@realDonaldTrump) October 18, 2018

Sadly, it looks like Mexico’s Police and Military are unable to stop the Caravan heading to the Southern Border of the United States. Criminals and unknown Middle Easterners are mixed in. I have alerted Border Patrol and Military that this is a National Emergy. Must change laws! — Donald J. Trump (@realDonaldTrump) October 22, 2018

Fear of immigrants has been a defining theme for Trump, as far back as the beginning of his presidential run when he called Mexican immigrants rapists and drug dealers. And other Republicans are hitting on similar themes in congressional races.

The New York Times published a story this week revealing that the Trump administration is considering rolling back recognition of transgender individuals, which would bar them from receiving civil rights protections on gender discrimination grounds.

To many, the announcement seemed designed to rile up conservative voters.

“The timing of the ... announcement, two weeks before the mid-term elections, suggests that this latest sensationalized attack on women and LGBT people—and transgender people in particular—is yet another cynical political ploy to sow discord and energize a rightwing base,” said Shannon Minter, the legal director for the National Center for Lesbian Rights.

GOP candidates nationwide are also running ads condemning black NFL players for protesting racial injustice by taking a knee during the national anthem, calling it unpatriotic. Trump has also used this issue to whip up his base.

And candidates of color have been facing all sorts of racist attacks this cycle, some more blatant than others. Florida Democrat Andrew Gillum, who would be the state’s first black governor if elected, is the subject of racist robocalls from a white supremacist group, and his GOP opponents warned voters not to “monkey up” the race by voting for him.

Bill Stepien, the White House’s political director, said the strategy is to portray the world as dangerous, and Republicans as the antidote.

“Voter satisfaction is the enemy of voter turnout,” Stepien told The Washington Post. “What’s changed is that while voters are still happy in the direction the president is leading the country, they’re angry at the way Democrats treated Justice [Brett] Kavanaugh, they’re scared when they hear Democrat after Democrat talking about socializing medicine and Medicare-for-All, and voters are plugged in as the president spends more and more time on the campaign trail.”

Candidates often turn to fear right before an election. Republicans tried in 2014 to use Ebola as an issue against Democrats, tying it to border security and blaming Obama for the spread of the virus.

“Gosh, can you imagine if Mitt [Romney] was the president right now? ... I guarantee you we would not be worrying about Ebola right now and, you know, worrying about our foreign policy screw ups,” said Republican Scott Brown, who was running for senator of New Hampshire at the time.