WASHINGTON, DC - JUNE 24: Speaker of the House Paul Ryan (R-WI) (C) addresses a news conference to introduce the House Republicans' tax reform proposal with House Ways and Means Committee Chairman Kevin Brady (R-TX) (5th L) and House Majority Whip Steve Scalise (R-LA) (3rd L) in the Rayburn Room at the U.S. Capitol June 24, 2016 in Washington, DC. Brady said that the GOP wants to 'bust up' the Internal Revenue Service, get rid of the estate tax and create a tax code so simple that Americans can file on a postcard-sized form. (Photo by Chip Somodevilla/Getty Images)

(FILES) This file photo taken on June 8, 2016 shows Democratic Presidential Candidate Bernie Sanders during A Future to Believe In rally in Washington, DC. Bernie Sanders said June 24, 2016 he will vote for Hillary Clinton in the US presidential election in November, bowing to his former rival for the White House but stopping short of a full endorsement.Asked on MSNBC whether he would cast his ballot for Clinton, the Vermont senator who waged a surprisingly tough campaign during the primaries said, "Yes." / AFP PHOTO / MOLLY RILEYMOLLY RILEY/AFP/Getty Images

In this photo obtained on June 23, 2016 from the twitter account of Representative Joe Kennedy III (D-MA), shows House Democrats holding a sit-in to call for a vote on stricter gun control laws at the Capitol in Washington, DC. Democratic lawmakers pushing for tougher US gun control laws after the Orlando nightclub massacre ended a stunning 24-hour sit-in at Congress on June 23, 2016. / AFP PHOTO / Representative Joe Kennedy III / Joe Kennedy III / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / Representative Joe Kennedy III/ HO" - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS JOE KENNEDY III/AFP/Getty Images

In this photo obtained on June 23, 2016 from the twitter account of Representative Joe Kennedy III (D-MA), shows House Democrats holding a sit-in to call for a vote on stricter gun control laws at the Capitol in Washington, DC. Democratic lawmakers pushing for tougher US gun control laws after the Orlando nightclub massacre ended a stunning 24-hour sit-in at Congress on June 23, 2016. / AFP PHOTO / Representative Joe Kennedy III / Joe Kennedy III / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / Representative Joe Kennedy III/ HO" - NO MARKETING - NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS JOE KENNEDY III/AFP/Getty Images

WASHINGTON, DC - JUNE 23: Rep. John Lewis (D-GA), (3rd L), James Clyburn (D-SC), Maxine Waters (D-CA) and Charles Rangel, (D-NY), right, speak with supporters outside the U.S. Capitol building June 23, 2016 in Washington, DC. Democratic House members ended their overnight House floor sit-in trying to force a vote on gun control legislation. (Photo by Allison Shelley/Getty Images) *** BESTPIX ***

WASHINGTON, DC - JUNE 23: US President Barack Obama walks away aftert speaking about today's Supreme Court ruling, at the White House June 23, 2016 in Washington, DC. The high court today announced that it was evenly divided in a case concerning President Barack Obama's controversial executive actions on immigration. (Photo by Mark Wilson/Getty Images) *** BESTPIX ***

WASHINGTON, DC - JUNE 23: U.S. Speaker of the House Paul Ryan (R-WI) answers questions during a press conference at the U.S. Capitol June 23, 2016 in Washington, DC. Ryan addressed the continuing sit-in on the floor of the House of Representatives by members of the House Democratic caucus during his remarks. (Photo by Win McNamee/Getty Images) *** BESTPIX ***

WASHINGTON, DC - JUNE 23: Kristan Hawkins, president of Students for Life, center, and other pro-life protesters clash with pro-choice protesters in front of the U.S. Supreme Court on a day where two important decisions on immigration and affirmative action were handed down by the court, on June 23, 2016 in Washington, DC. A decision in the case over a Texas law requiring clinics providing abortion services to meet the same building standards as walk-in surgical centers had been expected but was deferred. (Photo by Allison Shelley/Getty Images) *** BESTPIX ***