title: how can I plot two graphs in one coordinate system combining all the values of one column?
body: <p>I want to have one coordinate system but here is the problem:</p>
  <p>I have all the graphs from all my states in the dataset, in the right colors and in the legend only according to party, but still, it's 50 graphs.
  I want only two - one combining all the republican states and one combining all the democratic states.</p>
  <pre><code>corona_usa_simple &lt;- readr::read_csv(&quot;https://raw.githubusercontent.com/datasets/covid-19/master/data/us_simplified.csv&quot;)
  
  corona_us_states &lt;- corona_usa_simple %&gt;% 
  select(- FIPS, -`Country/Region`) %&gt;%  rename(State=`Province/State`)
  
  us_states_population &lt;- corona_us_states %&gt;%
      group_by(State, Date) %&gt;% 
      summarise(totalPopulation = sum(Population),
                totalConfirmed = sum(Confirmed),
                totalDeaths = sum(Deaths))
  
  wiki_governors &lt;- htmltab(&quot;https://en.wikipedia.org/wiki/List_of_United_States_governors&quot;,
   header = 2) %&gt;% slice(-1)
  wiki_governors[23,3] &lt;- &quot;Democratic&quot; #Democratic-Farmer-Labor to Democratic
  
  corona_party_states &lt;- left_join(wiki_governors, us_states_population, by= &quot;State&quot;) %&gt;%
  select(- Governor, - Born, - `Prior public experience`, - Inauguration, - `End of term`, - `Past governors`)
  corona_party_states &lt;- transform(corona_party_states, CasesPop = totalConfirmed*100000/totalPopulation) %&gt;%
    rename(state = State) 
  
  ## Plot for the graphs
  ggplot(data = corona_party_states) +
    geom_point(aes(x = Date, y = CasesPop, color = Party)) +
    scale_color_manual(values=c(&quot;Democratic&quot; = &quot;blue&quot;, &quot;Republican&quot; = &quot;red&quot;))+
    ggtitle(&quot;COVID-19 Cases per Capita by Party&quot;)+
    ylab(&quot;Cases/100K&quot;)+
    xlab(&quot;Timeline&quot;)+
    theme_bw()
  </code></pre>
  <p>This is my code so far. I would appreciate any help!</p>
  <p>I also tried this approach, but it looks just the same:</p>
  <pre><code>corona_party_cases &lt;- corona_party_states %&gt;% 
   group_by(Party, Date) %&gt;% select(-state) %&gt;% summarise(CasesPop)
  </code></pre>