More than 100 Conservative MPs voted against regulations to enforce standardised packs for cigarettes by May 2016, division list analysis has revealed.
In the free vote, the 104 Tory MPs - including Wirral's only Conservative MP Esther McVey - were joined by three members of the Labour Party, two Liberal Democrats, both Ukip MPs and two members of the DUP.
The measures were passed by a majority of 254 after being backed by 367 MPs.
The aye voters included 122 Tories, 192 Labour MPs and 37 Liberal Democrats, plus various other MPs.
David Cameron voted in favour, as did Ed Miliband - though Nick Clegg missed the division, which took place over 90 minutes in one lobby after being deferred from last night.
Justice Secretary Chris Grayling was among high profile opponents of the measures, as was Conservative veteran Ken Clarke.
After the vote, Mr Cameron's official spokesman said: "The Prime Minister voted in favour of this change. He is pleased that it has gone through."
Asked if the PM was disappointed at the number of Conservative MPs voting against plain tobacco packaging, the spokesman said: "The whole point of a free vote is that people can express their views freely."
Peers will vote on the measures on Monday.
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