3) President Obama was in Colorado for a second time in the past month on Wednesday, a signal of how important his team believes the state is for his reelection chances. This time, he touted his proposal to make student loan debt manageable. 2) Rep. Michael McCaul, R-Texas, will not make a Senate bid. He had been giving a run close consideration and his personal wealth would have made him an intriguing candidate. But McCaul ultimately said he could best serve Texas by remaining in the House, where he has seniority on the Homeland Security Committee. 1) Reversing course, Rep. Connie Mack, R-Fla., will run for the Senate, upending the Republican primary race. Mack said earlier this year that he would not run, and he threw his support behind state Senate President Mike Haridopolos, who has since dropped out of the GOP race. Mack has the ability to make a big splash in the field, as poll after poll shows a GOP electorate unimpressed or unfamiliar with the current Republican choices. But Mack's moderate stance on immigration could emerge as a major vulnerability for him in the contest. He recently compared the Arizona anti-illegal immigration law to Nazi Gestapo tactics.