Cameron hopes the limits will help stave off the likelihood of a vote to leave the EU in the event of a referendum.
As the below shows, the policy is also incredibly popular.
Each year, the polling company YouGov, in association with the Sunday Times, publishes its "policy knockout".
This competition pits a set of 16 policies against each other in pairs, with the most popular of each pair moving on to the next round until there is a winner.
Statista has mocked up the results for us in the above graphic, where you can see that a ban on migrants' benefits triumphs over the likes of renationalising the railways or the introduction of a living wage.
Interestingly, as YouGov's Peter Kellner points out, constitutional issues like an EU referendum or further devolution for Scotland do not appear as populist as politicians make them out to be - both falling in the first round.
There are flaws in this type of analysis - the initial placing of each policy can determine where it will end up in the competition.
For instance, a scrapping of HS2 may be one of the most popular policies around, but because it was placed against the even more popular renationalisation of the railways in the first round.
But it demonstrates why Cameron is so vigorously pursuing such a policy.