Pocketbook Issue

A “pocketbook issue” (like a “bread-and-butter issue”) is an issue that concerns voters because it directly affects their wealth. The term “pocketbook issue” is cited in print from at least 1900, but became popular when Calvin Coolidge said, in August 1924, that he would campaign for president on pocketbook issues.
 
The expression that people will “vote their pocketbooks” has been cited in the 1910s, but became popular after the New Deal in the 1930s.
 
A highly emotional and divisive issue (such as abortion) can be described as a “hot-button issue” (since 1970) or a “wedge issue” (since 1976). A central issue (such as a war or an economic depression) is a “paramount issue” (cited in print since 1844).
 
           
The Free Dictionary
pocketbook issue - an issue whose settlement will affect financial resources
 
(Oxford English Dictionary)
pocketbook, n. and adj.
adj. (attrib.).  Chiefly N. Amer. Relating to considerations of personal finance, esp. as a factor in politics.
1953 Holland (Mich.) Evening Sentinel 25 Nov. 10/7 Three Democratic senators predicted today that ‘pocketbook issues’ will play an overriding role in the 1954 congressional election campaign.
1960 Life 4 July 32/1 So where are any pocketbook issues for the Democrats?
     
Chronicling America
12 October 1900, Colfax (WA) Gazette, pg. 5 (supplement), col. 2:
Imperialism is no issue at all. There is only one issue in this campaign, and that concerns the business interests—the pocketbook issue. While people are threatened with another financial panic and business depression their thoughts are not going to be concentrated on any cry of imperialism.
 
13 August 1924, Chillicothe (MO) Constitution, pg. 1, col. 5:   
“POCKETBOOK ISSUE”
IS PARAMOUNT IS THE
BELIEF OF COOLIDGE
WASHINGTON, Aug. 13—President Coolidge believes the “pocketbook issue” is paramount in the coming campaign. Straight forward declaration for economy in government in reduction of taxation, it was learned from those close to him today, will constitute his main offensive against the issues launched by his opponent.
 
Google News Archive
29 March 1932, Deseret News (Salt Lake City, UT), “News Publishes First of 12 Stories by Special Observer on Balancing of Budget” by David Lawrence, pg. 4, col. 4:
And because tho problem of federal and state overlapping never been so vital and has never been so much of a pocketbook issue, not much progress has been made toward solving it.
 
29 October 1936, Chicago (IL) Daily Tribune, “New Deal’s tax on wages Cut Iowa support” by Arthur Evans, pg. 10:
...under the social security act, has developed into a predominant pocketbook issue affecting workers.
   
Google Books
15 June 1939, Pittsburgh (PA) Press, “Spartan Stuff,” pg. 14, col. 2:
They don’t relish each other’s society, or each other’s political views. But there at last is an issue on which they stand together—the personal pocketbook issue.
 
Google Books
Safire’s Political Dictionary
By William Safire
New York, NY: Oxford University Press
2008
Pg. 548:
pocketbook issue A voter’s concern with what is happening to his income and its buying power.