Updated at 3:21 p.m.

Rep. Maurice Hinchey (D-N.Y.) (Mike Groll/AP)

Hinchey will make the announcement official on Thursday at 1 p.m. eastern time, when he will speak at an historic sight in Kingston, N.Y., according to a release from his office.

Hinchey, 73, has received treatment for colon cancer and has been in poor health for some time. He had a second surgery this month, after which his spokesman declared that he was “cancer-free.”

He has represented his district, the 22nd, since 1992. He faced his toughest reelection race since the early 1990s in 2010, when he won with 53 percent of the vote, but his district isn’t a top Republican target.

His exit is just the latest x-factor in the state’s upcoming battle over redistricting. The state is losing two seats — probably one from upstate, where Hinchey’s district is, and one from the New York City area — but exactly which of the state’s 29 districts will get the ax is the topic of much debate.

Already, special-election-winning Reps. Kathy Hochul (D-N.Y.) in upstate and Bob Turner (R-N.Y.) in New York City appear to be prime candidates for elimination, given their lack of seniority. But Hinchey’s retirement means his district is perhaps the most attractive target for cutting, as most redistricting plans seek to keep incumbents safe.

Hinchey is the first member of Congress from New York to announce his retirement.

But we really have no idea which direction that state’s line-drawers will go. The state has yet to release any proposed congressional redistricting maps.

Adding to the uncertainty, Gov. Andrew Cuomo (D) has threatened to veto any plan that gerrymanders the new districts.

Hinchey is the 10th House Democrat to announce his or her retirement. Eight others are running for other office.

On the Republican side, six are retiring outright and seven are running for higher office.