CHICAGO (AP) — Longtime U.S. Rep. Bobby Rush has filed candidate petitions for Illinois’ March primary on the last day and could face a Democratic challenger.

Chicago Alderman Howard Brookins Jr. said Monday that he circulated petitions for the Chicago-area district because there was uncertainty about Rush, who waited to file until the deadline.

Brookins says he never intended to run against Rush, but filed petitions Monday and would make a final decision at a later date.

Rush was first elected to Congress in 1992 to the Democrat-heavy district.

Meanwhile, seven Democrats have filed to get on the primary ballot for U.S. Rep. Luis Gutierrez’s Chicago-area seat. Gutierrez announced last week that he wouldn’t seek re-election after 13 terms.

The candidates include Cook County Commissioner Jesus “Chuy” Garcia and two Chicago aldermen.