CNN's GUT CHECK for April 17, 2013

CNN's GUT CHECK | for April 17, 2013 | 5 p.m.
– n. a pause to assess the state, progress or condition of the political news cycle

BREAKING: INCREASED BACKGROUND CHECKS FOR GUNS FAILS… The U.S. Senate just voted down a compromise proposal to expand background checks on firearms sales. The bipartisan plan was brokered by Sens. Joe Manchin, D-West Virginia, and Pat Toomey, R-Pennsylvania, and was backed by President Barack Obama in his push for a package of gun laws in the aftermath of the Newtown school massacre. – Tom Cohen

ROSE GARDEN: President Barack Obama to delivers a Rose Garden statement on the failed vote at 5:30 p.m. ET.

DEVELOPING: 'SIGNIFICANT PROGRESS,' BUT NO ARREST IN BOMBING… Authorities investigating this week's Boston Marathon attack want to question a man who was seen on video wearing a white baseball cap, two official sources with knowledge of the investigation told CNN. One of the sources said the man had the hat on backwards and was wearing a light-colored hooded sweatshirt and a black jacket. The second source said that investigators have not identified this person. – Michael Pearson and Tom Watkins

MARKET WATCH: U.S. stocks end sharply lower, pulled down by banks and Apple, which dropped 6%. Dow falls 141 points.

MARK (@PrestonCNN) & DAN (@DanMericaCNN)
What caught our eye today in politics

As news continues to develop in the Boston Marathon bombing, envelopes containing ricin addressed to President Barack Obama and Sen. Roger Wicker, R- Mississippi, have been intercepted in offsite White House and Senate mailrooms. Here is what we know at this hour:

The Boston Marathon Bombing:

– Two days after explosives killed three people and wounded more than 180 during the Boston Marathon, details continue to trickle in as investigators sort through evidence.
– The FBI said in a statement Wednesday that no arrest has been made, “contrary to widespread reporting,” tied to Monday's Boston Marathon attack.
– After sources told CNN and several other news organizations that an arrest had been made, sources with the Department of Justice and Boston Police Department each said that no arrest had occurred.
– Investigators believe they have identified a suspect in the marathon bombings, a source who has been briefed on the investigation told CNN's John King. The possible breakthrough came from an analysis of video from a Lord and Taylor department store near the site of the second blast, and video from a Boston TV station helped as well, the official said.
– Authorities have received 2,000 tips from around the world, said Richard DesLauriers, the special agent in charge of the FBI's Boston office. "Someone knows who did this," he said.

Ricin Scare (reporting from Matt Smith and Carol Cratty):

– Letters containing ricin that were addressed to President Barack Obama and to Sen. Roger Wicker, R-Mississippi were discovered in offsite White House and Senate mailrooms.
– A law enforcement source told CNN the letters read: “To see a wrong and not expose it, is to become a silent partner to its continuance. I am KC and I approve this message.”
– Because initial tests can be "inconsistent," the envelopes have been sent off for additional tests, an FBI statement said. Those results were expected later tonight, an FBI official told CNN.
– Reports of suspicious packages and envelopes also came into two Senate office buildings late Wednesday morning. Capitol Police evacuated the first floor of the Hart Senate Office Building for more than an hour and questioned a man in the area who had a backpack containing sealed envelopes, but the man was not taken into custody.
– Mail for members of Congress and the White House has been handled at offsite postal facilities since the 2001 anthrax attacks, which targeted Sen. Patrick Leahy, D-Vermont, and then-Majority Leader Tom Daschle, D-South Dakota.
– “It just reminds you that with public service comes the real possibility that you could be a target,” said Sen. Pat Roberts, R-Kansas. “But on the other side of it, we have an excellent police force, and I think they'll get to the bottom of it.”
– “Suspicious letters” were also reported in two home-state Senate offices: Sen. Carl Levin of Michigan and Sen. Jeff Flake of Arizona.

the LEDE
Did you miss it?

Leading CNNPolitics: Delayed immigration rollout could face more opposition
A bipartisan plan to overhaul the nation's immigration system, in the works for months, faced delays this week as lawmakers and President Barack Obama shifted focus to the bomb attack in Boston. But the measure, which was formally filed for consideration in the Senate early Wednesday, already faces blowback from some opponents of immigration reform, who argue Monday's attack – which was committed by a yet unknown perpetrator – should be cause for reconsidering any reform making it easier for immigrants to gain citizenship.

Leading Drudge: Report: Suspect Identified
Investigators believe they have identified a suspect in the Boston Marathon bombing from security video and an official statement was expected later in the day, a law enforcement source said on Wednesday. – Tim McLaughlin

Leading HuffPo: Brink Of Collapse
Months of legislative work will come to a head on Wednesday at roughly 4 p.m. as the Senate takes up amendments to gun legislation that will determine both its reach and likelihood of passage. As of Tuesday evening, the landscape looked fairly bleak for those seeking new, stronger restrictions on sales, as late efforts to find an accord with rural lawmakers on an expansion of the background check system officially fell apart. – Sam Stein and Amanda Terkel

Leading Politico: Republicans pull plug on Sanford
National Republicans are pulling the plug on Mark Sanford’s suddenly besieged congressional campaign, POLITICO has learned — a potentially fatal blow to the former South Carolina governor’s dramatic comeback bid. Blindsided by news that Sanford’s ex-wife has accused him of trespassing and concluding he has no plausible path to victory, the National Republican Congressional Committee has decided not to spend more money on Sanford’s behalf ahead of the May 7 special election. – Alex Isenstadt

Leading The New York Times: Poison Feared in Letters Sent to Obama and Lawmakers
The Federal Bureau of Investigation said on Wednesday that a letter addressed to President Obama appeared to contain the poison ricin. The letter was intercepted at a screening facility outside the White House, the Secret Service said. – Mark Landler and Ashley Parker

TRAIL MOMENTS
The political bites of the day

- Obama: Thoughts remain with Boston -
PRESIDENT BARACK OBAMA AT A WOUNDED WARRIORS EVENT AT THE WHITE HOUSE: “We obviously meet at a time when our thoughts and prayers are with the people of Boston. Our hearts are with the families of victims, and now we send our support and encouragement to people who never expected that they'd need it - the wounded civilians, who are just beginning what I'm sure will be for some of them, a long road to recovery. It's a road that remarkable warriors and athletes here know all too well, and as a consequence, they're going to serve for all of the families as well as all Americans, a continued inspiration.”

- Toomey signals his fight for gun control is over -
REPUBLICAN SEN. PAT TOOMEY IN A WRITTEN STATEMENT: “I did what I thought was the right thing for our country. I sought out a compromise position that I thought could move the ball forward on an important matter of public safety. My only regret is that our amendment did not pass. It’s not the outcome I hoped for, but the Senate has spoken on the subject, and it’s time to move on. We have a lot of other very important issues to deal with such as getting the economy back on track, dealing with the debt ceiling and creating more jobs for Pennsylvanians.”

- NRA heralds no vote -
NRA INSTITUTE FOR LEGISLATIVE ACTION EXECUTIVE DIRECTOR CHRIS COX IN A WRITTEN STATEMENT: “As we have noted previously, expanding background checks, at gun shows or elsewhere, will not reduce violent crime or keep our kids safe in their schools. We are grateful for the hard work and leadership of those Senators who chose to pursue meaningful solutions to our nation’s most pressing problems.”

- Progressives to target Democrats who voted against Manchin-Toomey -
NEIL SROKA, COMMUNICATIONS DIRECTOR OF DEMOCRACY FOR AMERICA, IN A WRITTEN STATEMENT: “Democrats who were too cowardly to get on the right side of a 90-10 issue like universal background checks better believe that the progressives will remember their spinlessness on gun violence prevention come reelection time. The over 1 million members of Democracy for America nationwide work to elect progressive fighters, not U.S. Senators who can be cowed by the right-wing fringe and gun industry lobbyists like the NRA.”

- McCain: ‘Doing the right thing is always a reward in itself’ -
REPUBLICAN SEN. JOHN MCCAIN HONORS GUN LEGISLATION ARCHITECTS IN AN SPEECH ON THE SENATE FLOOR: “I want to congratulate both Sen. Manchin and Sen. Toomey for taking this position. You may not win today I say to my two colleagues, but I will say that you did the right thing. You did the right thing and it has been my experience as a senator in this body for some years who has not always done the right thing, but doing the right thing is always a reward in itself.”

- Rand Paul: Obama used Newtown families as 'props' -
REPUBLICAN SEN. RAND PAUL AT A WASHINGTON EVENT WITH REPORTERS: “In some cases, I think the president has used them as props.”

Gut Check Full Service: Press Secretary Jay Carney responds to Paul’s comments… “I don't know if Senator Paul met with the Newtown families, but the Newtown families aren't here for the president. They're here because their children were murdered. They're here asking for the Senate to do something that's common sense. That's my response.”

- Bipartisan House group makes immigration work public with statement -
A WRITTEN STATEMENT FROM DEMOCRATIC REP. XAVIER BECERRA: “Americans want to see the nation’s broken immigration system fixed, and they know it will take bipartisanship to solve this problem in a sensible and rational way. This week, a bipartisan group of senators stepped forward to introduce their proposal, and we applaud their effort. We are also working on a good faith, bipartisan effort in the House. We believe we will soon agree on a reasonable, common-sense plan to finally secure our borders and strengthen our economy with a tough but fair process that respects the rule of law so immigrants can contribute to our country. While we have made substantial progress, we continue to work diligently towards a bill that keeps America strong, competitive and true to our values.”

Gut Check Full Service: Members of the bipartisan group are Reps. Xavier Becerra (CA), John Carter (TX), Mario Diaz-Balart (FL), Luis Gutierrez (IL), Sam Johnson (TX), Raul Labrador (ID), Zoe Lofgren (CA), and John Yarmuth (KY).

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