Did UKIP cost the Conservatives their majority? - Part II

Via Tim Montgomerie, I discovered an article in The Times on this subject:

Analysis of results shows that in at least 21 key marginal seats, Ukip’s share of the vote proved enough to allow Labour or the Lib Dems to see off strong Tory challenges.

Whether 17 or 21 seats, all of the points in my previous post still stand.

The most interesting suggestion, highlighted by Montgomerie, comes from an old article by Janet Daley:

In the name of its own principles, UKIP should now feel morally obliged to withdraw its candidates from the general election – or at least from contesting any seat in which a Liberal Democrat might oust a Conservative. If it does not – and if it thus succeeds in depriving the Conservatives of a working majority and inflating the LibDem result by default - it will have been responsible for providing the most Europhile party in British politics with signficant power in a coalition government.