PROVIDENCE, R.I. — Rhode Island Secretary of State Nellie Gorbea says she cannot delay the state’s Sunday deadline to register to vote in the November election because it’s in the state constitution.

The U.S. Election Assistance Commission called Gorbea’s office this week after Democratic Sens. Charles Schumer of New York and Patrick Leahy of Vermont sent a letter asking the commission to investigate the deadlines in 10 states.

The senators say a 30-day federal registration deadline means it should be no earlier than Tuesday because mail cannot be postmarked on Sunday or Monday, the Columbus Day holiday.

Gorbea’s office says Rhode Island’s own 30-day registration deadline is in the state constitution. Residents can register online or visit drop-off sites Sunday.

Gorbea, a Democrat, says she’s willing to revisit the deadline in the future.