When Congressman Rob Andrews (D-NJ) announced two days ago that he'd be challenging incumbent Sen. Frank Lautenberg in the Democratic primary, a lot of readers from outside the state were probably ready to dismiss it as a non-starter — Lautenberg is a four-term Senator, after all, and it's only two months from now to the primary.

But the reality is, this could be a very serious challenge. Lautenberg is 84 years old, with many polls showing that voters think he's too old for the job. On top of that, New Jersey politicians are almost never truly popular, and Lautenberg isn't the exception.

The ambitious pol Andrews has a few things going for him: Relative youth, a lack of any statewide unpopularity, and the support of the South Jersey party organization — whose power is growing and whose zeal to defeat the North Jersey establishment, which has ruled the state since forever, is as feverish as it's ever been.

Andrews's support in South Jersey is typified in the backing of one of the state's most powerful fundraisers, George Norcross, who in many ways runs the South Jersey Democrats and has been mounting a real challenge to the Northern leaders.

"I'm very happy that he is supporting me," Andrews said, after he'd announced his candidacy. "The South Jersey Democratic Party has been solid and unified in my favor."

For example: Assembly Speaker Joe Roberts was at Lautenberg's big campaign kickoff on Tuesday — a show of force featuring practically the whole lineup of the state party's leadership, meant to scare Andrews off from the race. After endorsing Lautenberg on Tuesday, Roberts switched on Thursday to supporting Andrews, his fellow South Jerseyan.

So where does it stand now? Lautenberg has the support of Gov. Jon Corzine, Sen. Bob Menendez, and state Senate President Dick Codey — all Northerners. He also has the support of every incumbent House member except Andrews, and they span the state geographically but are mostly from the North. And of course, the DSCC will be actively supporting the incumbent.

Andrews meanwhile, looks to have the united South Jersey front he boasted of, with multiple legislative endorsements, Southern county organizations starting to come in for him, and even a handful of big supporters from up North.

But here is Andrews' problem: North Jersey has long dominated the state because they simply have more people. If the South Jerseyan is to take over, he's going to need to work very hard for the next two months. We'll see what happens then.