Question: Which Democratic US Senator set a record for margin of victory with 71.2% in the 2004 election only to be surpassed by Kirsten Gillibrand's 72% of the vote  in 2012?
Sentence (from "United States Senate election in New York, 2004"): Incumbent Democratic U.S. Senator Chuck Schumer won re-election to a second term with 71.2% of the vote, a then-record margin of victory for any statewide candidate in New York's history.
Relevant evidence: Yes