gganimate_reprex

# load packages
library(readr)
library(tidyr)
library(ggplot2)
library(gifski)
library(gganimate)
library(dplyr)

# load data
tst <- readr::read_csv("https://elpais.com/especiales/2019/elecciones-generales/encuestas-electorales/ficheros/tabla.csv?1554807308", 
                       col_types = cols(
                         date = col_date(format = "%d/%m/%y"),
                         house = col_character(),
                         sample = col_double(),
                         turnout = col_double(),
                         PP = col_double(),
                         PSOE = col_double(),
                         UP = col_double(),
                         Cs = col_double(),
                         ERC = col_double(),
                         PDC = col_double(),
                         PNV = col_double(),
                         PAC = col_double(),
                         BIL = col_double(),
                         CC = col_double(),
                         VOX = col_double(),
                         COM = col_double()
                       ))

# preparing and plotting 
gga <-
  tst %>% 
  select(date, house, PP, PSOE, UP, Cs, VOX) %>% 
  gather(key = partido, voto, PP, PSOE, UP, Cs, VOX) %>% 
  filter(!is.na(voto) & house %in% c('cis', 'celeste-tel', 'metroscopia',
                                     'gad3', 'invymark', 'sigma dos')) %>% 
  ggplot(aes(x = date, y = voto, color = partido)) +
  geom_line() +
  geom_point() +
  theme_minimal() +
  scale_color_manual(values=c("#EE9A00", "#27408B", "#8B1A1A","#A020F0", "#458B00")) +
  labs(x = 'Date', y = 'Vote estimation (%)', color = 'Political Party') +
  theme(legend.position = "bottom", 
        axis.text = element_text(size=12),
        axis.title = element_text(size=14, face="bold"),
        legend.title = element_text(size = 12, face="bold"),
        legend.text = element_text(size = 12),
        strip.text = element_text(size = 14)) +
  facet_wrap(~ house) +
  transition_reveal(date) + 
  shadow_mark()

# plot 
gganimate::animate(gga, height = 550, width = 900, nframes = 150)