Indiana Senate Republicans unveiled their redistricting proposal Tuesday for the state Senate district lines. The map will help decide who represents every Hoosier for the next decade.

Sen. Eric Koch (R-Bedford), the proposal’s chief architect, said the new map only splits 27 counties between districts, an improvement from 43 in the previous version. And it keeps 96 percent of all townships whole and 92 percent of cities and towns.

He also said some changes in the new map reflect input from Hoosiers during the statewide public hearings on redistricting last month. Examples Koch cited include keeping more of South Bend in one district and the entire city of Greencastle in a single district.

The Senate redistricting plan creates four open seats. It also draws four groups of incumbents into districts together:

• Sen. Frank Mrvan (D-Hammond) and Sen. Lonnie Randolph (D-East Chicago)
• Sen. Phil Boots (R-Crawfordsville) and Sen. Brian Buchanan (R-Lebanon)
• Sen. Mike Gaskill (R-Pendleton) and Sen. Tim Lanane (D-Anderson)
• Sen. Chris Garten (R-Charlestown) and Sen. Ron Grooms (R-Jeffersonville)

Grooms had previously announced his plan to retire after his term ends next year.

An analysis of the proposed Senate map projects Democrats will lose one district but gain a newly created seat, while another Democratic district becomes extremely competitive.

Meanwhile, Republicans appear unlikely to lose any seats while most of their incumbents are safer.

Senate President Pro Tem Rodric Bray (R-Martinsville) said Republicans aligned their priorities with what he said the public wants.

“In terms of compactness and keeping communities of interest together,” Bray said.

READ MORE: Analysis Says Indiana Redistricting Maps Among Worst Partisan Bias In Country

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But critics point to the proposal splitting West Lafayette and Lafayette into two separate districts and carving up the south side of Fort Wayne into three different Senate seats as evidence to the contrary.

The Senate Elections Committee will hold a public hearing on the map Monday.

Contact reporter Brandon at bsmith@ipbs.org or follow him on Twitter at @brandonjsmith5.