Early in this Senate cycle attention has been focused on the news that four Republicans will not seek re-election in 2010. In a way of course, this is good news. Knowing about these retirements early gives NRSC Chairman John Cornyn (R-TX) plenty of time to line up credible candidates. And it appears that the GOP is assured of fielding very strong candidates in competitive open seat races in Florida, Missouri, Kansas, and Ohio. It also appears very likely that Republicans will run strong and experienced campaigners in Colorado, New York, Illinois, and Delaware. Today Cornyn got a welcome piece of good news: the Democrats could not get their strongest candidate to take on New Hampshire incumbent Judd Gregg: