5) Rep. Steven LaTourette, R-Ohio, won't run for reelection. LaTourette was one of the leading moderates in the Republican caucus, and reportedly decided to step down over a committee assignment dispute. LaTourette has scheduled a 10 a.m. press conference for this morning, where he may explain his decision. Roll Call reports that if LaTourette submits his resignation after August 8, his GOP replacement on the ballot would be chosen by party officials within the district. With an also-ran Democratic candidate on the ballot, the GOP replacement will be favored to hold the seat for Republicans. 4) It's runoff day in Texas! Check out our preview of the GOP Senate showdown between David Dewhurst and Ted Cruz, and don't miss our preview of key House races. Stay tuned to Hotline on Call tonight for full results. 3) A late get for former Rep. Ciro Rodriguez, who's facing state Rep. Pete Gallego in the Texas-23 Democratic runoff: Bill Clinton threw his support to the former congressman on the eve of the runoff. 2) Massachusetts Democratic Senate nominee Elizabeth Warren is scheduled to be the prime-time lead-in for Bill Clinton's speech at the Democratic National Convention on Sept. 5, the DNC announced on Monday. Sen. Scott Brown's campaign spun the time slot as Warren "getting bumped" from delivering the keynote (it was rumored she was under consideration to make that speech). In a release, they connected it to comments Warren made last year that they have been tying to President Obama's "you didn't build that" comment. The Boston Globe headline: "Elizabeth Warren to speak before Bill Clinton at Democratic convention, but will not deliver keynote." 1) Democratic National Convention officials will announce this morning that San Antonio Mayor Julián Castro, a rising star in American politics, will become the first person of Hispanic descent to serve as the keynote speaker at the party's quadrennial convention.