President Trump’s drive to secure Republican advantage in the House through mid-decade redistricting — and Democrats’ move to retaliate with their own efforts to redraw political lines to their advantage — could supercharge the partisan shift in Congress.

Should the efforts succeed, they would amplify the trend of one party gaining a stranglehold on state congressional delegations, intensifying the deep polarization that has helped to paralyze Congress in recent years.

Even before multiple state legislatures, goaded by Mr. Trump, began to consider redrawing their maps, the number of House delegations represented by a single party was at a 60-year high.

A sudden new round of redistricting would continue a remarkable shift of one party gaining congressional supremacy in a state through gerrymandering and ideological shifts, leaving the opposition barely represented or shut out entirely. The result would have profound implications for Congress.

“The number has been on the rise basically since 2010, when Republicans roared back after Obama’s victory,” said Eric Ostermeier, a researcher at the Humphrey School of Public Affairs at the University of Minnesota, who tracks the political makeup of congressional delegations. “Red states are getting redder, blue states are getting bluer. All this data points to this getting worse.”