Sources: Possible suspect sought in Boston bombing  —  After the explosion: Moment-by-moment  —  (CNN) — Investigators scrambling to solve the fatal bombings at the Boston Marathon want to question a man seen on video as a possible suspect in the attack, two official sources with knowledge of the investigation said Wednesday.

Senate rejects background checks on gun purchases in 54-46 vote  —  The Senate delivered a devastating blow to President Obama's agenda to regulate guns Wednesday by defeating a bipartisan proposal to expand background checks.  —  It failed by a vote of 54 to 46, with 5 Democrats voting against it.

Feds arrest suspect in ricin-positive letters sent to Obama, senator  —  The ricin-laced letters sent to President Obama and Mississippi Sen. Roger Wicker were both postmarked April 8 and sent from Memphis, Tenn., signed “I am KC and I approve this message.”  A third letter went to Michigan Sen. Carl Levin.

Republicans pull plug on Mark 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 …

Texas teacher claims she couldn't have fondled black student because she's racist  —  A teacher in Texas has invoked her own racism in a defense against charges that she fondled an African-American student in her first grade class at Northwest Preparatory Academy Charter School in Humble.

Move Over “Obama Phone,” Say ‘Hola!’ to the Marco Rubio Immigration Phone, AKA MarcoPhone  —  With the new ‘Border Security, Economic Opportunity, and Immigration Modernization Act’ finally being filed in the U.S. Senate, concerns over how much money the immigration reform bill will cost …

High Schooler Protests ‘Slut-Shaming’ Abstinence Assembly Despite Alleged Threats From Her Principal  —  A West Virginia high school student is filing an injunction against her principal, who she claims is threatening to punish her for speaking out against a factually inaccurate abstinence assembly at her school.

Ron Paul Institute opens amid split with Rand  —  'He has his opinions.  You'll have to ask him where he disagrees.  Not me,' says Ron Paul.  AP Photo  —  Close  —  Ron Paul made an impassioned plea for shuttering Guantanamo Bay Wednesday at a launch event for his new Ron Paul Institute for Peace and Prosperity.

Alleged McConnell Bugger Visited White House  —  Days before Progress Kentucky launched a Twitter offensive against Mitch McConnell, its executive director met with White House officials.  —  Via: J. Scott Applewhite / AP  —  WASHINGTON — The head of a group accused of illegally taping private meetings …

Assault Weapons Ban, High-Capacity Magazine Measures Fail In Senate Vote  —  WASHINGTON — Democrats helped Senate Republicans defeat major reforms to reduce gun violence Wednesday, including bans on certain assault weapons and high-capacity magazines.  —  An amendment, put forth …

Updated: Wife of ex-JP confesses, says her husband shot former Kaufman DA, his wife and top prosecutor  —  Kim Williams' Facebook profile photo, believed to be quite dated.  (Facebook)  —  Update 12:25 p.m.: Kim Williams' arrest warrant says she confessed to the entire plot, explaining her role and saying her husband was the shooter.

Tom Friedman Continues His Journey To Insanity (The Terrorists Win)  —  Times columnist and global raconteur Tom Friedman outdoes himself as he tries to put the Boston bombing into perspective:  —  Bring on the Next Marathon  —  By THOMAS L. FRIEDMAN  —  ...