Every few months, Gallup asks voters if they identify as Democrats, Republicans, or something else. For respondents who say they are something else, they are then asked if they lean toward either the Republican Party or the Democratic Party.
During the last few months, the percentage of voters who identify as Democrats, or who say they lean toward the Democratic Party, has remained the same, at 45%. The percentage of voters who identify as Republicans, or who say they lean toward the Republican Party, has dropped from 40% to 38%. See the results here. The poll was taken during May but only released on June 6. Thanks to Political Wire for the link.
Silly, all Gallop does is report on plurality votes, so of course the cannot show proportionate figures, they can only show rhetoric which centers around pluralism. So there is no way to report, or no way out, of pluralism reporting under Gallop Co. reporting.
Are you interested in pure proportional representation (PR)?
The 10th USA Parliament has been counting and reporting pure proportional representation correctly for more than 22 consecutive years and it works fine:
http://www.usparliament.org
Now there is also the new global United Coalition of Candidates:
http://international-parliament.org/ucc.html
Nobody has it as good as the United Coalition.
OTOH, the main listing for Gallup party-affiliation poll history is here:
http://www.gallup.com/poll/15370/Party-Affiliation.aspx
And the May 2017 survey, compared to the one in April, shows gains for Rs away from Is with Ds steady — and the Is who yield to the pressure of the “leaning” question split 45-44 R.
(I still think that, if pollsters get to lean on Is, they should also have to ask Rs and Ds something similar — how often they vote the candidate over the party, maybe, or which party they’d really like to vote for if they had a chance (the voters or the parties, take it either way).
“That to preserve the unity, the team should always mention the names of all ten candidates who are working together for the good of the ALL and to mention only the top ranked names for the five State offices, would not be in the interest of unity”.
Jeffrey Drobman, PHD (Democrat) Former Candidate for CA Secretary of State (6/3/2014), United Coalition of Candidates 2014:
http://international-parliament.org/ucc-2014.html