BOSTON >> Talk of Democratic U.S. Sen. Elizabeth Warren as a possible running mate for presumptive presidential nominee Hillary Clinton is throwing a fresh spotlight on Massachusetts' process for filling an empty Senate seat.

Warren is in the fourth year of her first six-year term and if she is elected vice president, she would be leaving her seat vacant in a year when Democrats are hoping to retake the Senate.

It would also spark the state's third special election for a Senate seat since the death in 2009 of Democratic Sen. Edward Kennedy after 47 years in office.

Before his death, Kennedy sent a letter to state lawmakers urging they change the special election law to let the governor — then Democrat Deval Patrick — name an interim appointment to the seat while a special election was held.

Democrats were also trying to maintain a 60-vote, filibuster-proof margin in the Senate ahead of any debate on President Barack Obama's health care overhaul.

The change was approved and Patrick named former Democratic National Committee Chairman Paul Kirk, a longtime Kennedy confidante, to the temporary post. Republican Scott Brown ultimately won the special election, but was defeated two years later by Warren.

The 2009 change came just five years after Democrats had changed the succession law to create a special election and block then-Gov. Mitt Romney, a Republican, from naming a temporary replacement if Democratic U.S. Sen. John Kerry had won his campaign for president.


In 2013, Massachusetts had another special election after Obama tapped Kerry to serve as Secretary of State. Patrick named his former chief of staff William "Mo" Cowan to temporarily fill the seat. Democrat Edward Markey won the special election.

With the GOP again holding the corner office at the Statehouse, some are wondering if Democrats would try to change the law yet again to block Gov. Charlie Baker from naming a fellow Republican to the seat until a special election could be held to elect someone to fill out the final two years of Warren's term.

By law, Baker would have to call a special election within 145 to 160 days of the date the vacancy occurs. That would mean Baker could appoint a Republican to hold the seat for the first few months of a potential Clinton administration.

Also, a Baker appointee could run for the seat permanently — something Kirk and Cowan pledged not to do — and perhaps use the temporary incumbency to gain a slight leg up on a Democratic opponent.

Democratic House Speaker Robert DeLeo told reporters recently that he wasn't keen on tinkering with the law, but also said it was premature to speculate.

"Haven't thought about it a whole lot," the Winthrop Democrat said. "But I'm not sure if I'd be terribly enthusiastic about changing what we've already done."

In 2009, DeLeo defended giving Patrick the right to make an interim appointment, saying he wanted to make sure "Massachusetts has their voice heard on health care, on the environment, on clean energy."