In the UK, the term used to be "a Socialite Socialist."
"Liberal" has a totally different political flavour over here than on the other side of the pond. Used to be a very central-ish, very minority party. Now, many of their policies are, indeed, to the left of soi-disant "New Labour" (pardon me whilst I wash my mouth out.)
But in the good-old bad old days, Labour was a fairly "socialist" (i.e., left wing) party, and there were (and are) a number of even further left organisations, inhabited by many real working-class activists, but also quite a lot of middle-class types (much like Tony Blair, indeed) who preached socialism but most certainly did not practice it. These were scathingly referred to aas "Socialite socialists," especially when they had to leave political meetings early in order to go to a "society" party or couldn't join the picket line because they were going hunting that day.
