Always with these polls, take a step back, look at trends, and look at past election results.
Basically, 42% has been enough to lead in this country to stonking majorities. Notice UKIP is on 10%. Now who knows exactly who they take their support from, however most guess they hurt the Tories more than Labour. If less than half the UKIP support is former Tory, then they are denying the Tories a majority the president of a banana republic would be proud of.
THEN AGAIN, exactly where is that 10% LibDem support? Put simply, if those 10% live in the wrong places - ie say London or the Midlands, then this will wipe out LibDem seats in the SW and North, quite possibly wiping out the party