Ron Richard has had a career in politics with few parallels.

He currently serves as president pro tempore of the Missouri Senate and was previously speaker of the state House. Only a handful of politicians in American history have served as the top leader in both of their states' chambers. 

For that accomplishment, Richard has term limits at least partially to thank.

Missouri's term limits are among the strictest in the nation, with a maximum of eight years of service allowed in the House or Senate. As a result, the state legislature sees a lot of turnover. Next year, more than a quarter of Missouri's representatives -- 27 percent -- will be prevented from running for re-election.

That constant churn, Richard suggests, has made lawmakers less cooperative.

"I think that’s why I’m a little bit jaundiced about term limits,” Richard told St. Louis Public Radio. “You can’t make a deal with somebody because everybody knows you’re going to be gone, so people don’t need to keep their word.”

All told, term limits will make a total of 271 state legislators in 24 chambers ineligible to run in 2018, according to an analysis by Ballotpedia. Like state legislatures as a whole, the affected chambers are tilted strongly toward the GOP. Republicans control 19 of the 24 chambers where term limits will have an impact.

"This year, it's really lopsided -- far more than we've seen in the past," says Charles Aull, Ballotpedia's state legislative project director. "Republicans have about twice as many term-limited legislators as Democrats do."

Many of the legislators who will be term-limited out of office in 2018 are in states with eight-year caps. That means members of the so-called Tea Party Class of 2010 -- when Republicans made sweeping gains across most of the country -- are already facing the end of their careers in their current legislative posts.

Despite the opening of lots of seats, Democrats shouldn't count on vacancies on the GOP side leading to lots of opportunities for pickups, says Ballotpedia's Aull.

"I wouldn't expect these term limits to have a significant impact on the partisan breakdown of these chambers," he says.

It's possible, however, that term limits will help Democrats rebuild their numbers to some extent. They're not likely to win back the Missouri House, for instance, but perhaps they'll be able to erode the GOP's supermajority there, says Aull. And every seat will matter in narrowly-held chambers, such as the Maine and Colorado Senates (where Republicans have a one-seat majority in each) and the Maine House (where Democrats have a two-seat advantage).

In strong Republican districts with open seats, Aull expects "we'll see a lot more contested primaries." It's possible Tea Party veterans will be replaced by new members with a Trumpist bent -- or perhaps old school "establishment" Republicans will regain some ground.

Term limits will have the greatest impact next year in Michigan, where 68 percent of the state senators can't run for another term. Michigan Senate Majority Leader Arlan Meekhof said earlier this year that term limits have been a "failed social experiment." Like Richard, Meekhof said limits had the effect of making legislators short-sighted since they won't be in office long enough to answer for the consequences of bad policymaking.

There's no doubt that many will run for other offices. Ahead of filing deadlines, it's hard to say for sure. But it's been the case with term limits in general that they haven't brought about a renaissance in citizen legislators. Instead, political pros are coming in with their eyes already set on their next desired gigs.

"You get extremely politically ambitious people," says Marjorie Sarbaugh-Thompson, co-author of the new book Implementing Term Limits: The Case of the Michigan Legislature. "They come in as freshmen with a clear outline of the next offices they're running for."

Prior to term limits, some members of the Michigan Legislature, which is considered a full-time, professional body, would stick around for decades in one chamber or the other. Term-limited legislators aren't in office long enough to gain real expertise, says Sarbaugh-Thompson, who teaches political science at Wayne State University.

There are three chambers where term limits are in place yet no legislator is being term-limited out next year: the Nevada Senate and both chambers in Arkansas. There's already been a good deal of upheaval recently in both states. Control of the Nevada Senate has changed hands twice since 2014. In Arkansas, where Democrats controlled both chambers as recently as 2012, Republicans now hold three-quarters of the seats.

The bigger change affecting Arkansas, however, was to the term limits law itself. In 2014, Arkansas voters approved an ethics package that included an extension for legislative terms. Rather than being limited to six years in the House and eight years in the Senate, legislators can now serve up to 16 years in either chamber, or both cumulatively. 

California voters approved a similar change in 2012. But no state has repealed term limits outright since Wyoming in 2004.

Any term-limit changes in Missouri or Michigan will come too late to help Sens. Richard or Meekhof. Both will be term-limited out next year.