Rally Round the Flag, Boys!

Doing a GOOGLE search on this phrase - Rally Round the Flag, Boys! - brings up numerous hits, almost all of which focus on political drama, and using a flag as a symbol to call to arms supporters to defend, support, and justify an extremist view or stand.
That said, it has absolutely nothing to do with the rest of this post EXCEPT that I was looking for a catchy phrase for the Title.

One of my neighbors came to me the other day to let me know that there will be a political rally for Angélica Araujo, Diputada Federal III Distrito Candidada on our street on Saturday, 30 Mayo from 6-10pm. And that our street will be closed between 77 and 79, that's calle 70 if you want to come see a political rally.

Terrific, we have a visitor coming in on a 9pm flight.
(just means we need to move the car in the afternoon,
and may have to park a block away after her flight arrives)

I've been noticing an abundance of PRI Verde campaign banners and stickers around the neighborhood. Also, the only election flyers we receive are for PRI Verde, hmmmmm!
I thought ms Araujo was PRI Verde, but on her website there is an X through the PRI Verde logo. Another confusion for me is the use of the OK signal, which seems to be used by ms Araujo and her campaigners, and supporters. You know the one, your thumb and index finger create a circle, and the other three fingers sort of stick up - I thought this was considered an obscene gesture here in México.

So much I don't know about Mexican politics.