There isn’t — at least yet — much quantitative evidence to demonstrate that Mayor Bloomberg’s popularity is soaring. But the sense we get from our own informal soundings is that the mayor is gaining ground with the public. Some of that may be attributed to the recovering economy. Some of it is no doubt the result of his plans for a tax rebate, and of his determination to stand firm in the face of the city’s public employees unions, which held a huge rally yesterday outside City Hall. The police officers and firefighters and public school teachers all want raises, and we don’t fault them for advocating their interests.

But it is the mayor’s job to advocate the interests of the taxpayers. And in an environment in which there are five applicants for every opening to teach in the schools, and in which the waiting list to get a job as a city firefighter is years long, the mayor deserves some credit for his efforts to hold the line.

The market for labor works for mayors as well as for firefighters and teachers and policemen, and what the mayor’s popularity indicates is that the voters recognize that their interests and those of the unions do not necessarily coincide.