JEFFERSON CITY – When the 2010 census numbers came out, one thing was certain: Missouri would lose a seat in Congress. And because Republican state lawmakers controlled the redistricting process, it was almost equally as certain that the displaced congressman would be a Democrat.

Indeed, Democratic U.S. Rep. Russ Carnahan found himself out of a job after the new maps were used in in the 2012 elections. Because of the redrawn districts, Republicans further strengthened their hold on Missouri's congressional delegation while contributing to the GOP's advantage in the U.S. House.

As Missouri's eight members of Congress prepare to seek re-election this year, the effects of redistricting still can be seen. None of the incumbents appear likely to draw a stiff challenge, because they all represent districts tailored to their partisan bents.

Missouri's redistricting results have mirrored what happened nationally.

As a result of victories in the 2010 elections, Republicans controlled a majority of state legislative chambers when it came time to redraw congressional districts based on the latest census figures. In many cases, they redrew maps to concentrate Democrats into a limited number of districts.

Nationally, Democratic candidates for the U.S. House received 1.4 million more votes than their Republican opponents in the 2012 elections, the first under the new districts. Yet Republicans won a 33-seat majority in the U.S. House.

In Missouri, Democrats went from holding three seats to two seats after the 2012 elections, when Missouri's total number of districts dropped from nine to eight because the state's population growth lagged that of the nation. Missouri's redrawn congressional districts were enacted when the Republican-led Legislature got the help of a few urban Democrats to override a veto by Democratic Gov. Jay Nixon.

The two remaining Democratic districts – one in St. Louis, the other, the 5th District, stretching from Kansas City eastward into some rural counties and including Eastern Jackson County – have a higher concentration of Democratic voters than they did previously. The concentration of Republicans in the six other districts was diluted under the new maps but remains strong enough so that all of those districts still tilt toward the GOP.

Republican state Sen. Scott Rupp, who led that chamber's redistricting efforts, said the high concentration of Democrats in the St. Louis district is partly the result of a federal Voting Rights Act prohibition against diluting minority votes. Blacks comprise 49 percent of the voting age population in Missouri's 1st Congressional District, compared with a 43 percent white population.

Rupp said the congressional districts also reflect a "migration of votes across the state," in which Democratic voters have congregated in urban areas while Republicans have spread to the outer suburbs and rural areas. "That's just how it is. The whole state's red and you have these blue earrings in Kansas City and St. Louis," said Rupp, who lives in the outer St. Louis suburb of Wentzville.

But there were alternatives that could have given Democrats a better chance in congressional elections. Political science professor David Kimball, of the University of Missouri-St. Louis, testified in 2012 in a lawsuit challenging Missouri's redrawn districts. Although the Supreme Court ultimately disagreed, Kimball believes the districts are unconstitutional because they are not compact enough. He supported an alternative map that would have kept an additional district rooted in the St. Louis area. That might have given Democrats a better shot at winning a third seat.

But Kimball said he doubts redistricting made a dramatic difference on the nation's public policy. "If Republicans had not had control of the redistricting process in so many states, their majority would have been smaller than it is, but I think they still would have had a majority," Kimball said.