Rep. Charlie Melancon (D-La.) is falling behind in the money chase for his run against Sen. David Vitter (R-La.).

Melancon announced Thursday that he raised just $600,000 in the fourth quarter, which is about half the $1.2 million raised by Vitter. Melancon saw his fundraising fall off since the third quarter, when he announced $750,000 raised after entering the race in late August.

Vitter also has more than twice as much cash on hand -- $4.5 million to $2 million.

Perhaps aware that its haul fell short, Melancon's campaign sought in its press release to compare his position now to those of three winning Democratic Senate candidates in 2008 -- Sens. Jeanne Shaheen (D-N.H.), Kay Hagan (D-N.C.) and Jeff Merkley (D-Ore.). But that comparison only goes so far.

It's true that he has plenty more cash on hand than any of them did at the end of 2007, but all three of them were starting from scratch, whereas Melancon already had $1.3 million in his House account at the end of June.

Shaheen raised $1.2 million in the fourth quarter of that year, while little-known state legislators Hagan and Merkley raised about as much as Melancon did, without being members of Congress.

Melancon won't have more money than Vitter, but getting out the message about Vitter's personal problems will take funds. He has some money, but he's not raising it as fast as his party would probably prefer.