Tuesday 1 March 2016: Massachusetts Primary. Hours 7:00a-8:00p EST (1200-0100 UTC). Some municipalities may open their polls as early as 5:45a EST. Delegate Selection: Proportional Primary. Voter Eligibility: Modified Primary.

Primary
Source: Secretary of the Commonwealth of Massachusetts.
Status: Official. Retrieved: Saturday 16 April 2016.
Included in Nationwide vote.

Tuesday 1 March 2016: All 42 of Massachusetts' delegates to the Republican National Convention are proportionally allocated to presidential contenders based on the statewide results of today's Presidential Primary. A mandatory 5% threshold is required in order for a presidential contender to be allocated National Convention delegates. [Plan for the selection of delegates Section IV 4.2]

NOTE as to rounding: after the number of votes for each presidential contender receiving at least 5% of the vote statewide is divided by the total votes cast for all presidential contenders receiving at least 5% of the vote statewide, the resulting percentage is applied to the total number of pledged delegates from the Commonwealth and then rounded to the nearest whole integer. Should the total number of delegates resulting from this procedure be either more or less than the total number of pledged delegates to which the Commonwealth is entitled, the qualifying candidates receiving the most or least votes statewide, respectively, will receive or lose one delegate each until the total number of delegates so distributed among candidates equals the total number of pledged delegates to which the Commonwealth is entitled (39).

Primary
Source: Secretary of the Commonwealth of Massachusetts.
Status: Official. Retrieved: Saturday 16 April 2016.

Trump: 42 delegates × 312,425 ÷ 600,621 = 21.847 delegates. Round to 22.
Kasich: 42 delegates × 114,434 ÷ 600,621 = 8.002 delegates. Round to 8.
Rubio: 42 delegates × 113,170 ÷ 600,621 = 7.914 delegates. Round to 8.
Cruz: 42 delegates × 60,592 ÷ 600,621 = 4.237 delegates. Round to 4.

In addition, 3 party leaders, the National Committeeman, the National Committeewoman, and the chairman of the Massachusetts's Republican Party, will attend the convention as pledged delegates by virtue of their position.

All delegates ... whose selection is made ... by ... Presidential Primary ... shall vote on the first such roll call for that presidential candidate unless released by such candidate. [G.L. c.53, §70I] [Plan I. 1.4]

Saturday 30 April 2016: Congressional District Conventions. 27 District delegates (3 from each of the state's 9 CDs) are elected according to the results of the primary.

Find the results here.

CD 1-- Trump: Kevin Jourdain, Dan Allie; Cruz: Bill Gillmeister.
CD 2-- Trump: Bonnie Johnson, Bill McCarthy; Rubio: Deb McCarthy.
CD 3-- Trump: Dean Cavaretta, Pat Hackmer; Cruz: Jeanne Kangas.
CD 4-- Trump: Kathy Carr, Trump Charles Grillo; Kasich: Ginny Greiman.
CD 5-- Trump: Mike Stopa, Angela Griffin; Kasich: Madison Crawford.
CD 6-- Trump: Arete Pascucci, Amy Carnevale; Rubio: Harry Loomos.
CD 7-- Kasich: Dianna Ploss, James Davidson; Trump: Thomas Leonard.
CD 8-- Trump: Geoff Diehl, Louis Murray; Rubio: Ken Narif.
CD 9-- Trump: Mark Townsend, Chris Sheldon; Rubio: Jeff Beatty.
Total-- Trump 17, Kasich 4, Rubio 4, Cruz 2.

Wednesday 25 May 2016: State Committee Meeting. 12 delegates (10 At-Large plus 2 bonus) are elected according to the results of the primary.

Current law sets the Presidential Primary to the 1st Tuesday in March and the Partisan Primary to 7th Tuesday [20 September 2016] preceding the November General Election [The General Laws of Massachusetts, Title VIII, Chapter 53: Section 28.].

Billl H.574, sponsored by James J. Dwyer, was filed on 14 January 2013. The bill changes Chapter 53, Section 28 to read "State primaries shall be held on the second Tuesday in August... Presidential primaries shall be held on the first Tuesday in March..."

Billl H.575, sponsored by James J. Dwyer, was filed on 14 January 2013. The bill changes Chapter 53, Section 28 to read "State primaries shall be held on the first Tuesday after the first Monday in June... Presidential primaries shall be held on the first Tuesday after the first Monday in June..."

H.551, introduced by state Representative James J. Dwyer (Democratic) on 10 March 2015, would (1) move the Presidential primary from the 1st Tuesday in March to the 1st Tuesday after the 1st Monday in June and (2) move the partisan primary from the September (in 2012 and 2014 laws were passed to hold the primary on 6 September and 9 September respectively) to the 1st Tuesday after the 1st Monday in June.

H.609, introduced on 10 March 2015 by state Representative Ellen Story (Democratic), would establish ranked voting for military and overseas absentee Presidential primary ballots - "... permit the voter to rank the candidates in order of choice."