The Levin-Reed withdrawal amendment has failed 47-47. In June, a Levin-Reed amendment for withdrawal could not overcome a filibuster at 52-47. Who switched their votes? No senator switched from opposition to Levin-Reed to support. The following switched from support to opposition:

Dodd (D-CT)
Nelson (D-NE)
Pryor (D-AL)
Collins (R-ME)

Republicans Hagel (NE), Snowe (ME), and Smith (OR) backed this measure. Six senators did not vote: Bennett (R-UT), Domenici (R-NM), Lott (R-MS), Boxer (D-CA), Durbin (D-IL), and Sanders (I-VT). These 6 presumably break 3 in favor (the Democrats) and 3 against (the Republicans). Some had expected Levin-Reed to get more support for this vote. The latest draft of Levin-Reed required troop withdrawals to start within 90 days--rather than the 120 days of an earlier draft.
Dodd says he opposed this draft of Levin-Reed because it does not require a "complete redeployment."