Of these, the parties won the same wards last year, except Labour took Roe Lee and Meadowhead wards from the Conservatives,and Marsh House from the Lib Dems, and the Lib Dems held Sudell, which was won by Labour in 2010.
The census figures thread was justified by the Tories' problems getting votes from ethnic minorities, and the same may also be true in Blackburn with Darwen. Most demographic change in the period 2001-2011 occured in North/Central Blackburn, with the Asian/Asian British population growing in the centre and spreading out into the more affluent areas to the north of the town e.g. Roe Lee, Corporation Park, Beardwood. Almost no change occurred in Darwen and south-western areas of Blackburn(Livesey,Fernhurst,Meadowhead). The Conservative position appears to have weakened in Beardwood, Roe Lee voted Labour in 2011/12, and Corporation Park has gone now from the Tories- I doubt it is now winnable even in a landslide year. Meanwhile the Conservatives remain strong in Livesey and Fernhurst(though much of the latter is new housing and it is a fairly new ward), and have strengthened in Meadowhead(relative to the rest of the town)- I wouldn't rule out a hold next year.
For next year, all Labour seats look safe, with the possible exception of Sudell(Lib Dem in 2011/12). Labour will most likely gain the third seat in Roe Lee, but I'm not sure about Meadowhead this far out. Lib Dems could possibly hold Marsh House- the defeats there haven't been catastrophic, but it's too early to say.
Related to earlier point: Meadowhead: 2002- Lab Maj0.4% 2012-Lab Maj6.8% Beardwood and Lammack;2002-Con Maj63.4%,2012-Con Maj23.2%(also a green standing in 2012) Corporation Park:2002- roughly even ,with other candidates,2012- Lab Maj 25.8%(was 55.8% in 2011!)
Relevant white British census %(2001/2011)
Beardwood and Lammack 87.1/60.7 Corporation Park 54.8/29.9 Meadowhead 96.4/94.8
Only four Liberal Democrats across a large borough - that's bad.
Four more than in Tameside!
Tameside has been a very week area for Lib Dems for many years. When I lived there about 12 years ago there was just one chap and his wife: then they split up acrimoniously and he was exposed as a former mercenary!
Blackburn with Darwen on the other hand had quite a strong Lib Dem group, who at one time were (briefly) part of a ruling coalition.
As in several other areas, the Lib Dems were artificially boosted during the later Blair years by defections in the Asian community. Even the Tories in B&D tried putting out leaflets in various languages targeting Jack Straw over the war.