He attended Star of the Sea Parochial School, graduated from St. Francis College, and took a course at Brown's Business School.
Then he joined his father's business, and later set up his own dock-building company.
On January 4, 1883, he married Margaret Magdalen Kidney (1862–1944), and they had five children.
Cronin was a member of the New York State Senate (5th D.) from 1909 to 1912, sitting in the 132nd, 133rd, 134th and 135th New York State Legislatures; and was Chairman of the Committee on Banks from 1911 to 1912.
He died on February 15, 1933, at his home at 8070 Narrows Avenue in Brooklyn, of a heart attack; and was buried at the Holy Cross Cemetery there.