Local council elections 2010: What will higher turnout mean?
Holding local and national polls on the same day will mean that millions of people who otherwise would not vote in council polls will do so. This is generally assumed to favour Labour whose core supporters are less likely to turn out and vote than those of either the Conservatives or the Liberal Democrats. Andy comments on the likely impact of higher turn out in The Guardian:
“I don’t think it’s quite as simple a story now as ‘Labour comes back’, but you can still reasonably expect that the higher turnout will help them.”