So disappointing:

Delaware attorney general Beau Biden announced Monday that he will not seek election to the U.S. Senate seat once held by his father, Vice President Joe Biden.

The younger Biden told supporters in an e-mail that he will run for re-election as attorney general rather than seek the Senate seat his father held for 36 years. [...]

"I have a duty to fulfill as attorney general, and the immediate need to focus on a case of great consequence. And that is what I must do," Biden, 40, wrote. "Therefore I cannot and will not run for the United States Senate in 2010. I will run for re-election as Attorney General."

The Senate seat is now held by Ted Kaufman, Joe Biden's longtime confidante and former Senate chief of staff, who was appointed by Delaware's then-governor to serve in an interim capacity until the 2010 election. Kaufman last week reiterated the pledge he made upon being appointed that he would not be a candidate in 2010.

Kaufman was appointed specifically to be a placeholder so Beau Biden could run after returning from Iraq. Now Biden's not willing to work for this seat.

Democratic governors had four chances to appoint Senators following the 2008 election, and all four screwed up. Now former Republican Governor Mike Castle is going to be heavily favored to win the seat in Delaware, although we should have a fighting chance in a D+7 state. It would have been better to name Delaware Lieutenant Governor John Carney to this seat.

UPDATE: Swing State Project has moved this race from tossup to lean Republican.

A new Research 2000 poll of the Delaware Senate race shows Republican Congressman Mike Castle and Attorney General Beau Biden virtually tied:

Research 2000 for Daily Kos. 10/12-14. Likely voters. MoE 4% (no trend lines)

Beau Biden (D) 45
Mike Castle (R) 46

Well, it couldn't be any tighter than that in this marquee matchup. Castle easily leads other potential match ups (Castle 51 Kaufman 37, Castle 49, Carney 41, Castle 51 Coons 39), but the Biden-Castle one is most likely because the political establishment loves its monarchies, and so do the voters. Interestingly, while Castle has solid Republican support (82-9), Biden gets less than three-quarters of Democrats (72-21). Independents lean toward Castle (48-40). If Biden brings Democrats home, it gets much harder for Castle to win.

I would bank on a sizable number of Democrats coming home if Biden runs for his dad's old Senate seat.

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The National Republican Senatorial Committee has recruited the only person able to make the U.S. Senate race in Delaware competitive next year. Congressman Mike Castle, a former governor who has never lost an election, will seek to serve out the remaining four years in the term to which Joe Biden was re-elected in 2008.

Meanwhile, Delaware Attorney General Beau Biden has safely returned from Iraq and is expected to announce his candidacy for the Senate seat. Castle has led Biden in three polls, but the most recent one (by Republican pollster Rasmussen) had Castle ahead by just five points, 47-42.

Swing State Project is now calling this race a tossup. There's a great discussion going on in that thread.

According to Taegan Goddard's Political Wire, the Cook Political Report also rates this race a tossup, while the Rothenberg Political Report is calling it "Lean Takeover."

Biden will have to fight for this one, although he won't be as big an underdog as his father was the first time he ran for U.S. Senate in 1972.

It's too bad that Democrats will have to invest resources in holding this seat (now represented by placeholder appointee Ted Kaufman). On the plus side, we are very likely to win the at-large House seat Castle will be vacating.

Update [2009-10-6 17:43:45 by desmoinesdem]: Public Policy Polling's first take since Castle's announcement:

When we polled the state in March Castle was leading Biden 44-36. But not surprisingly his name recognition was also ten points higher. Among respondents who had an opinion of Biden, whether it was positive or negative, the Democrat led 43-41. And the undecideds in such a scenario were 64% Democratic to 12% Republican, as well as 35% African American.

So Castle's early poll leads are largely a function of name recognition, and given his nearly 30 years in statewide office really aren't that substantial.

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The Hill is reporting that Rep. and former Gov. Mike Castle (R-DE) will announce today that he is officially running for Delaware's open Senate seat in 2010.

Castle's decision gives Republicans a major recruiting win and a strong possibility of picking up a Democratic-held Senate seat for the first time since 2004.

But his entry will not guarantee the seat goes to Republicans. Castle will most likely face a tough challenge from Delaware Attorney General Beau Biden, the vice president's son, who has been rumored to be contemplating a bid while serving in Iraq over the past year.

No reliable polls have been taken recently, but strategists in both parties acknowledge that a Castle-Biden showdown would instantly become one of the most competitive races in the country. Both men are widely popular in the state.

Chuck Todd is calling this a "HUGE recruiting coup for the GOP." Castle's entry into the race has led Stu Rothenberg to move it to toss-up.

An early March Public Policy Polling (D) survey had Castle leading Biden 44%-36%. Susquehanna Polling & Research (R) showed Castle up 55%-34% in late April. And a Sept. 30 Rasmussen Reports poll had the Republican ahead 47%-42%. The latter survey also showed that both men are very well-liked. Castle was at 61% favorable/34% unfavorable and Biden 60% favorable/32% unfavorable.

We're moving the Delaware Senate seat from Currently Safe for Democrats to Lean Takeover for the GOP. However, even if Beau Biden takes a pass on the contest, the combination of the state's Democratic bent and Castle's popularity strongly suggest a very competitive contest.

Two thoughts. First, something I haven't seen Rothenberg, Todd, or The Hill mention: this gives us an extremely strong pick-up opportunity in the House. Second, with baby brother possibly heading to Afghanistan following Friday's graduation from Marine boot camp, I know who my first donation of the 2010 Senate cycle will be: a progressive Iraq vet who's tough on child molestors.

Update:The Cook Report has moved Castle's open House seat to to "leans Dem."

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Delaware's at-large seat in the House of Representatives is the second-most Democratic-leaning House district currently held by a Republican, but perhaps not for much longer. Local newspaper columnist Ron Williams says Representative Mike Castle will run for Joe Biden's old Senate seat in 2010:

Expect a public announcement in the next month.

Castle is not yet talking, but there are a number of high-ranking Republican operatives who know Castle's moods and inclinations, and they say hands down that he's in for the seat now held by Ted Kaufman, Biden's former chief of staff. Kaufman is stepping down in 2010.

If I owned a ranch, I'd bet it on a Castle candidacy.

(Hat tip--shudder--to the National Review Online.)

Delaware Attorney General Beau Biden is expected to seek the Democratic nomination for his dad's old seat, but Williams wrote that Biden might sit the race rather than run against the popular Castle.

Then again, jason330 of the Delaware Liberal blog says Williams is a "well known dumbass," so take this speculation with a grain of salt. But Castle is probably the only Republican who could make this a race, and he is being heavily recruited by the NRSC.

UPDATE: Thanks to BENAWU for the reminder that Louisiana's second district is actually the most Democratic-leaning seat currently held by a Republican--though that shouldn't last long either.

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