The Virginia Senate passed a constitutional amendment Friday to pave the way for a mid-decade redistricting push, the final legislative step needed to send it to voters for approval.

If voters support the amendment, which is expected to appear on the ballot this spring, Virginia’s Democratic-controlled Legislature would be able to redraw the state’s congressional map before the midterm elections.

The measure would amend the state’s Constitution to allow lawmakers to temporarily bypass Virginia’s bipartisan redistricting commission and alter the state’s congressional lines if another state does the same outside the usual decennial redistricting cycle or a court order.

Virginia Democrats, who currently control six of the state’s 11 districts, are hoping they could net an additional three or four seats through the process.

The National Democratic Redistricting Committee, which is led by former Attorney General Eric Holder, has shown people involved in the effort more than two possible maps, a source familiar with the process said.

One map could elect as many as 10 Democrats in a favorable election year for the party, the source said, while others were more likely to elect nine Democrats.

Virginia Democratic lawmakers have said they will release a proposed map this month.

The push in Virginia comes in response to President Donald Trump pressuring GOP-led states across the country to redraw their maps to shore up the party’s narrow House majority. Six states enacted new district boundaries last year, with the biggest Democratic counterpunch coming in California.

Florida Republicans are also hoping to pick up an additional three to five seats through a redistricting effort this spring.

The process in Virginia has been uniquely complex. Lawmakers needed to pass the amendment during two separate legislative sessions, with an election in between. So after passing the measure before last November’s elections, both chambers took it up this week as lawmakers returned to Richmond.

The amendment must appear on the ballot at least 90 days after final passage, which would be April 16. Since Virginia’s primaries are slated for June, lawmakers will need to call a special election this spring for a new map to be in place this year.