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 …

Humble first-grader says teacher sent kids out, fondled her  —  A first-grade teacher at an Humble prep school cited her racial prejudice against black students in denying allegations that she fondled a girl in her classroom last month, according to court records.

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.

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  —  ...

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.

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 …