A new poll from Daily Kos of the Delaware Senate landscape shows a tight race in the offing should Attorney General Beau Biden (D), as expected, face Rep. Mike Castle (R).

General Election Matchup
Castle 46
Biden 45
Undecided 9

This is the first poll taken since Castle announced his run. The nine-term Congressman and former Delaware governor leads among independents 48-40, and also has the support of one-in-five Democrats. Biden leads among voters 18-29 (48-42 percent) and 30-44 (47-44 percent), and has a 10-point edge among women.

Biden, son of the vice president, just returned from a year serving in Iraq, and has said he is focused on spending time with his family and resuming work as Attorney General. But this morning, he said he signaled that he was indeed looking to run.

"Am I considering it? Absolutely," he said on Good Morning America. "But I'll be making that decision in due course."

In the event Biden does not run, the poll tested matchups featuring Ted Kaufman, appointed to replace Joe Biden this January; former Lt. Gov. John Carney, who is now running for Castle's seat; and New Castle County Executive Chris Coons:

Castle 49 -- Carney 41 -- Und 10
Castle 51 -- Coons 39 -- Und 10
Castle 51 -- Kaufman 37 -- Und 12

Favorable Ratings
Castle 64 / 30
Biden 65 / 29
Kaufman 36 / 26
Carney 41 / 19
Coons 34 / 8

The survey of 600 likely voters was conducted by Research 2000 from October 12-14, and has a margin of error of +/- 4 percent.

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