It's a paradox. The airwaves are awash in political news, yet political experts say voter turnout in Thursday's state and county primaries might hit a historic low. Nevertheless, important legislative seats on Beacon Hill, as well as key county positions will be filled. Here's what to look for in Eastern Massachusetts as voters go to the polls.

Look no further that just over the river for a hot state Senate race in Cambridge, Somerville and Medford, a district that's known as a hotbed of progressive voters. The fight between incumbent Sen. Patricia Jehlen and Cambridge City Councilor Leland Cheung is being waged on the left's left.

If Cheung's name sounds familiar it's because he ran for lieutenant governor in 2014.

But the two names on the ballot have been overshadowed by the big money forces that are at work for them: Teachers unions have spent upwards of $100,000 to keep Jehlen in office while a pro-charter school expansion group has backed Cheung with nearly the same amount.

All this to win a pro- or anti-charter seat in the Senate that couldn't even get the House to entertain its compromise charter cap expansion bill this past session. The question of whether to raise the limit on charter schools in the state will be answered directly by voters on the November ballot, an even costlier affair.

In Boston proper, the longest serving women in the Legislature is stepping down and making way for one of three women of color to join the House. The competitive House race in Roxbury and the Fenway neighborhood to replace the retiring Rep. Gloria Fox is a three-way mix where, again, the charter question is playing a big roll.

Marydith Tuitt is a longtime aid for Fox running on a record of dedication to and knowledge of the district's needs in the State House. Monica Cannon, a teacher's union-backed community counselor is waging an outsider race and shoring up support from those opposed to expanding charters. Chynah Tyler is running as a native progressive with her own State House experience as an aide to Sen. Sonia Chang-Diaz and is backed by pro-charter groups.

Fox is the only black woman in the House and all three Democrats vying for the seat are also women of color.

Sen. Dan Wolf is stepping away from the Senate, but he has no plans to disappear. Wolf told WGBH last week that though he's not actively thinking about running for another office after he leaves the Senate, he does plan to dedicate himself to expanding prekindergarten on the Cape and speaking out about the role fundraising plays in Massachusetts politics. The progressive businessman and founder of Cape Air is seen by some Beacon Hill watchers as a potential candidate to take on Gov. Charlie Baker in 2018. Wolf is keeping his options open for the next cycle, saying the earliest he'd think about a further office is early next year. 

Competitive primaries are sparking interest on both the Democratic and Republican sides to replace Wolf and represent most of the Cape and Islands.

On the Democratic side, Truro's Julian Cyr has worked for the state's Public Health Department. He's a native son (his family runs a popular restaurant in Truro) and has support from the strong LGBT community in that part of the state. Don't discount the inroads he's made on Beacon Hill by working for the state government, as the Deval Patrick administration alum has been tapping fundraising opportunities in Greater Boston.

Sheila Lyons is also from the outer Cape in Wellfleet, but as a Barnstable County Commissioner, she's more established district-wide than her opponent. Lyons may do better in the denser parts of the cape and islands and has built a county-wide base to work from.

Whoever wins the Democratic nomination will be thrown into a tough general election fight because Cape Cod is one of the more conservative parts of the state. Even though Wolf is about as progressive as it gets, Republicans have more than a fighting chance in the redder areas closer to the mainland.

Barnstable Town Councilor Jim Crocker is running on his business background and maintains construction and real estate companies in the area. He's running on ten years of town government experience on a Charlie Baker-esque platform of boosting towns, small business growth, government efficiency and opiate treatment.

His opponent, Anthony Schiavi, has one of the better resumes in any race this year. He's a retired Air Force brigadier general who went from running the Cape Cod military base to work as town manager and police commissioner of Ashland.

Issues most of the candidates agree voters want their next senator to work on are of course opiates which are ravaging the Cape, environmental issues and care for elders.

Cape Cod will be the local political epicenter Thursday, with two House races to fill empty seats in the Lower Cape and and Islands districts.

The seven-way race for the Democratic nomination to become the next Suffolk County Register of Deeds is a bit of a circus featuring everyone from a defeated veteran city councilor, a pair of perennial also-rans and a few outsiders who might have some interest in performing the $124,000 a year job. 

Former Boston City Councilor Stephen Murphy could walk away with a primary victory as a well-known politician in a very crowded field on a low turnout election day. The other candidates, Stephanie Everett, Katherine Forde, Paul Nutting Jr. and Jeff Ross, have fought to stand out in the crowd in the face of Murphy's name recognition advantage.

Perennial candidates Douglas Bennett (he of the hand-made green signage) and Michael Mackan are also hoping to notch their first Boston wins in the race.

Suffolk County Sheriff Steve Tompkins got a reprieve from having to run against Bennett this time around and is instead faced with a challenge from transportation company owner Alexander Rhalimi. Rhalimi is running on making the sheriff's department's $108 million budget more transparent to voters.

Tompkins has served as sheriff since 2013 and has been outspoken on issues on criminal justice reform and ways to prevent recidivism.

The sheriff's post oversees local jails for Boston, Chelsea, Revere and Winthrop.

As Secretary of State William Galvin predicted Tuesday, turnout is expected to be low, about 8 to 10 percent.