A  Commonwealth Court judge has rejected a Democratic request to put a new candidate on the March 21 special election ballot for the state House's 197th District.

Judge Anne E. Covey, who last week removed from the ballot the original Democratic candidate, Frederick Ramirez, after ruling that he did not live in the North Philadelphia district, on Friday said the party's replacement candidate was chosen too late for the election.

The ruling leaves the Republican nominee, Lucinda Little, as the only candidate in the 197th District, where Democrats hold 85 percent of the voter registration, Republicans have 5 percent, and independents and smaller political parties hold 10 percent.

The Democrats on Monday put forth Emilio Vazquez, leader of the 43rd Ward, who is now on leave from his job as a Philadelphia Parking Authority revenue auditor, as a replacement for Ramirez.

Covey, in her 10-page ruling, noted that effort came three weeks after the Feb. 6 state deadline to nominate a substitute candidate.

Covey, a Republican, also wrote that the Democrats "had options available" when Ramirez's residency was originally challenged Feb. 2, including selecting a replacement at that time.

Adam Bonin, attorney for Vazquez and the Democratic Party, said Covey's decision will be appealed "immediately" to the state Supreme Court.

"Judge Covey's decision places political parties in an impossible position when it comes to dealing with ballot challenges, and deprives the voters of the 197th of their right to a fair choice on the ballot on March 21," Bonin said in an email.

The Democrats had argued that substituting a candidate would not disrupt the election. The Department of State, which rejected the nomination for Vazquez, offered in court that it was simply following the Pennsylvania Election Code.

Linda Kerns, the Republican City Committee's associate general counsel, filed the original challenge to Ramirez's residency and opposed in court the effort to replace him with Vazquez.

Another Commonwealth Court judge previously ruled that Green Party nominee Cheri Honkala would not be listed on the ballot because her nomination papers were filed one day late. Honkala appealed that decision to the state Supreme Court, which on Friday in a 4-3 decision rejected her bid to get on the ballot. She has vowed to run a write-in campaign for the seat.

The 197th District seat is open because former State Rep. Leslie Acosta, a Democrat, pleaded guilty to a federal embezzlement charge last year but waited until Jan. 3 to resign from the Assembly.