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Election commission workers prepare ballot boxes and election materials for the presidential election scheduled for Sept 28, at the Independent Election Commission compound in Kabul, Afghanistan, Sunday, Sept. 15, 2019. Afghan officials say around 100,000 members of the country's security forces are ready for polling day. (AP Photo/Rahmat Gul)

Democratic presidential candidate Elizabeth Warren, D-Mass., speaks during a rally on Tuesday, Sept. 10, 2019, in Austin, Texas. (Nick Wagner/Austin American-Statesman via AP)

FILE - In this July 15, 2019, file photo, from left, Rep. Rashida Tlaib, D-Mich., Rep. Ilhan Omar, D-Minn., Rep. Alexandria Ocasio-Cortez, D-N.Y., and Rep. Ayanna Pressley, D-Mass., speak at the Capitol in Washington. All are American citizens and three of the four were born in the U.S. President Donald Trump told American congresswomen of color to “go back” to where they came from. He later vowed to revive a racial slur to tear down Elizabeth Warren, promoted a wild conspiracy theory linking a past political opponent to the death of a high-profile sex offender and blamed Friday’s stock market slide on a low-polling former presidential candidate. (AP Photo/J. Scott Applewhite, File)

FILE - In this Aug. 10, 2019, file photo, Democratic presidential candidate former Vice President Joe Biden speaks in Des Moines, Iowa. (AP Photo/Charlie Neibergall, File)

Afghan security personnel stand guard at the site of a deadly attack in Kabul, Afghanistan, Sunday, July 28, 2019. Afghan officials say the political offices of the president's running mate were hit by a large explosion and stormed by an unknown number of attackers. Nasrat Rahimi, the interior ministry spokesman, said vice-presidential candidate and former intelligence chief Amrullah Saleh survived the attack. (AP Photo/Rahmat Gul)

President Donald Trump speaks to members of the media before boarding Marine One helicopter on the South Lawn of the White House in Washington, for the short flight to nearby Andrews Air Force Base, Md., Friday, July 19, 2019. (AP Photo/Pablo Martinez Monsivais)

This undated product image obtained by the Associated Press shows Nike Air Max 1 Quick Strike Fourth of July shoes that have a U.S. flag with 13 white stars in a circle on it, known as the Betsy Ross flag, on them. Nike is pulling the flag-themed tennis shoe after former NFL quarterback Colin Kaepernick complained to the shoemaker, according to the Wall Street Journal. (Nike via AP Photo)

President Donald Trump walks through the Colonnade of the White House, next to Polish President Andrzej Duda, as they arrive for a news conference in the Rose Garden, Wednesday June 12, 2019, in Washington. (AP Photo/Jacquelyn Martin)

In this Saturday, June 1, 2019 photo, a passing bicyclist pauses to watch supporters of Denver Mayor Michael Hancock as they pause for a picture during a rally for the incumbent in Denver. Hancock, who is seeking his third, four-year term as mayor, is facing Jamie Giellis in a runoff Tuesday. (AP Photo/James Anderson)

FILE - This Thursday, Jan. 3, 2013, file photo shows Google's headquarters in Mountain View, Calif. The U.S. Justice Department is readying an investigation of Google’s business practices and whether they violate competition standards, according to news reports. The search giant was fined a record $2.72 billion by European regulators in 2017 for abusing its dominance of the online search market. In the U.S., the Federal Trade Commission made an antitrust investigation of Google but closed it in 2013 without taking action. (AP Photo/Marcio Jose Sanchez, File)