Suppose I have some text like this,
text<-c(\"[McCain]: We need tax policies that respect the wage earners and job creators. [Obama]: It\'s harder to save
I think this technically answers what you've asked, but you probably want to add a \\:
to the end of the regex for prettier text (removing the colon and space).
library(stringr)
str_replace_all(text, "\\[.+?\\]", "")
#> [1] ": We need tax policies that respect the wage earners..."
vs...
str_replace_all(text, "\\[.+?\\]\\: ", "")
#> [1] "We need tax policies that respect the wage earners..."
Created on 2018-08-16 by the reprex package (v0.2.0).