Polls are open: 7 a.m. to 8 p.m. If you are unsure where to vote, find your polling place online.
Voters can cast ballots in either the Republican, Democrat, Green or Libertarian primary, depending on official party affiliation. Independents can choose to vote in the Democrat or Republican primary.
There is a statewide race to be the Democrat running for the U.S. Senate and a bunch of races to join the U.S. House of Representatives for Massachusetts. As this is Massachusetts - the bluest of the blue states - most of the races are for Democrats.
Below are some of the elections voters will decide today. Most ballots will also include uncontested races not listed here.
U.S. SENATE
Incumbent Sen. Ed Markey is facing challenger Rep. Joe Kennedy III to be the Democrat on the November ballot for a seat at the U.S. Senate.
U.S. HOUSE (Including Western and Central Mass Representatives)
District 1: Incumbent Rep. Richard Neal is facing challenger Holyoke Mayor Alex Morse in a race that has drawn national attention. It may be a bellwether, politicos say, to how progressive agendas could play in November.
District 4: Democrats are running to replace Rep. Joe Kennedy III who gave up his House seat to run for the Senate. On the ballot will be Jake Auchincloss, Jesse Mermell, Becky Grossman, Alan Khazei, Ihssane Leckey, Natalia Linos, and Ben Sigel.
District 6: Incumbent Rep. Seth Moulton is facing challengers Angus McWuilken and Jamie Belsito.
District 8: Incumbent Rep. Stephen Lynch is facing challenger Robbie Goldstein.
MASSACHUSETTS STATE HOUSE
In Springfield, Democrat candidates Denise Hurst, Sean Mullan, and Orlando Ramos are running to replace incumbent Rep. Jose Tosado.
In Lawrence, incumbent state Rep. Frank Moran is facing challenger Marianela Rivera.
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