Jim Bunning has been telegraphing bad fundraising numbers for some time now, especially with his public admission last month that his fundraising was "lousy." With the numbers he released today, we can see the full scope of "lousy:" he raised $263,000 in the first quarter, and has $375,000 cash on hand. This looks like the Bunning campaign starting to enter a death spiral: perceptions that he can't win lead to low fundraising, which leads to perceptions that he can't win (and certainly that's not helped by polls showing him losing by double digits).
Also, bear in mind this is less than his potential Dem challenger Lt. Gov. Dan Mongiardo has; Mongiardo raised more than $429,000 last quarter (although Mongiardo will need to spend a lot this year to stay competitive with AG Jack Conway in the primary). And while you might be thinking $263K can still go a long way in a cheap state like Kentucky, that's not quite true; Kentucky is a very inefficient state for advertising dollars, as you have to pour a lot of money into the Cincinnati and Evansville markets, so blanketing Kentucky costs more than the cost of blanketing some states with significantly larger populations.
Still, Bunning is rich as Croesus compared with fellow Republican Tom Coburn of Oklahoma. Coburn reports having raised all of $17,000 in the first quarter, and holds $57,000 cash on hand. While Coburn has been making public noises lately about being unsure about whether to run for re-election (saying yesterday that he was seeking divine guidance on the issue, as well as saying that "Being a doctor is more fun"), these numbers speak pretty loudly on the issue.
http://www.swingstateproject.com/diary/4789/kysen-oksen-lousy-and-lousier