Twelve-term Congressman Jim Saxton will not run for re-election next year, PoliticsNJ reports, citing health reasons for his retirement. Saxton is being treated for prostate cancer and sciatica. First elected in 1984, Saxton started his career in the state assembly in 1975.

Saxton, a socially and economically moderate Republican, has been targeted by the DCCC in recent months after winning in 2006 with 58% of the vote, a narrower margin than some had expected. Saxton had cruised to victories over even top DCCC recruits. This year, the DCCC was trying again and had recruited State Sen. John Adler, seen as another top recruit. Adler has already banked an impressive $229,000, though far out-paced by the nearly $1.4 million Saxton has on hand.

The third district, which covers Philadelphia's New Jersey suburbs out to Ocean and Burlington Counties and includes Fort Dix, has become a swing district in recent presidential years. Al Gore carried the district by a 54%-43% margin in 2000, while George Bush beat John Kerry by a narrow 51%-49% margin in 2004. As an open seat, the district will become a top priority for both parties.

Adler will face the winner of what is likely to be a competitive Republican primary. State Sen. Diane Allen, who ran for Senate in 2002, is the likely front-runner, while PoliticsNJ reports that Burlington County Sheriff Jean Stanfield, Ocean County Clerk Carl Block and Ocean County Freeholders John Kelly and Joe Vicari are also considered contenders.

Update: Politico's Josh Kraushaar reports that Wyoming Rep. Barbara Cubin, who along with her husband has faced serious medical issues this Congress, will also announce her retirement at a GOP central committee meeting in her state tomorrow. Cubin narrowly survived in 2006 after threatening to slap one of her opponents, who is in a wheelchair. She beat Democrat Gary Trauner by just half a percent last year.

The seat is safer than Saxton's for Republicans, and Cubin's retirement makes State House Majority Leader Colin Simpson, son of former Senator Alan Simpson, a strong favorite to win the GOP nod. Simpson had already declared his intention to run for the seat, regardless of Cubin's plans. Trauner is running again as well.