Select change column value if in list - mysql

Question

I am trying to query my table to count the number of votes and if the voting method is in list ['C', 'M', 'S', 'L', 'T', 'V', 'B', 'E'] then count it as one and replace the voting_method to 'L'.
Right now I have the following query which returns the right results but doesn't take care of the duplicates.
select `election_lbl`, `voting_method`, count(*) as numVotes
from `gen2014` group by `election_lbl`, `voting_method` order by `election_lbl` asc
election_lbl voting_method numVotes
2014-09-04 M 1
2014-09-05 M 2
2014-09-05 S 1
2014-09-08 C 16
2014-09-08 M 5
2014-09-08 S 9
2014-09-09 10 5
2014-09-09 C 46
2014-09-09 M 4
2014-09-09 S 5
2014-09-10 C 92
2014-0g-10 M 3
2014-09-10 S 7
2014-09-11 C 96
2014-09-11 M 3
2014-09-11 S 2
2014-09-12 C 104
2014-09-12 M 10
2014-09-12 S 3
2014-09-15 C 243
2014-09-15 M 18
2014-09-15 S 3
2014-09-16 10 1
2014-09-16 C 161
2014-09-16 M 4
2014-09-16 S 3
2014-09-17 C 157
2014-09-17 M 5
2014-09-17 S 12
You can see that for 2014-09-05 I have two voting_method M and S both of which is in the list. I want the ideal result to remove the duplicate date field if the values are in the list. So it would be 2014-09-05 'L' 3. I don't want the vote for that date to disappear so the results should count them as one.
Changed the query to this but mysql says wrong syntax.
select `election_lbl`, `voting_method`, count(*) as numVotes from `gen2014`
(case `voting_method` when in ('C', 'M', 'S', 'L', 'T', 'V', 'B', 'E')
then 'L' END) group by `election_lbl`, `voting_method` order by `election_lbl` asc
Table Schema
CREATE TABLE `gen2014` (
`voting_method` varchar(255) DEFAULT NULL,
`election_lbl` date DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Answer 1

SELECT election_lbl
, CASE WHEN voting_method IN ('C','M','S','L','T','V','B','E')
THEN 'L'
ELSE voting_method END my_voting_method
, COUNT(*)
FROM my_table
GROUP
BY my_voting_method -- or vice
, election_lbl; -- versa

Answer 2

If you just want the total votes using those methods for each date, listed as method 'L', then do not include method in the group by, and have the SELECT select 'L' as voting_method
select `election_lbl`, 'L' AS `voting_method`, count(*) as numVotes
from `gen2014`
where voting_method IN ('C', 'M', 'S', 'L', 'T', 'V', 'B', 'E')
group by `election_lbl`
order by `election_lbl` asc

Answer 3

select x.`election_lbl`, x.`voting_method`, count(*) as numVotes
from (
select `election_lbl`,
CASE when `voting_method` in ('C', 'M', 'S', 'L', 'T', 'V', 'B', 'E')
then 'L'
else `voting_method`
END as `voting_method`
from `gen2014`) x
group by x.`election_lbl`, x.`voting_method`
order by x.`election_lbl` asc