Sorry you are right it is now a Labour-Tory marginal, probably a swing seat, ie if the Tories ever got a majority in parliament they'd have to win it. LibDems lost it to Tories in 1987 who held it in 1992, Labour won it in 1997 with a healthy 4,840 majority.
I was confusing it with Pendle which does have the town of Colne in it (just to confuse us!). Pendle was Tory until 1992, when it was won by one-time carpet-bagging Labour apparatchik Gordon Prentice, who stacked up a 10,000 majority in 1997 and surprised everyone by going anti-Blair. Also now somewhat marginal.