Second-term Rep. Kristen Gillibrand (D) is set to be appointed to succeed Secretary of State Hillary Rodham Clinton in the Senate, New York news outlets reported Thursday night.

New York Gov. David Paterson (D) is scheduled to make the appointment at a noon news conference Friday in Albany.

Gillibrand had been considered a dark-horse candidate for the Senate appointment until Caroline Kennedy’s abrupt withdrawal from the Senate sweepstakes.

After Kennedy’s withdrawal, speculation had focused on state Attorney General Andrew Cuomo (D). But Gillibrand’s stock had risen in recent days and she had been the focus of an attack by an anti-gun control group.

Rep. Carolyn McCarthy (D-N.Y.) told the New York Times on Thursday that she would run against Gillibrand in a primary if her fellow Congresswoman were selected the Senate appointee. McCarthy’s signature issue has been gun control ever since she was elected following her husband’s shooting death on the Long Island Railroad in 1993.

Gillibrand’s upstate district is conservative-leaning and Republicans believe they can compete in a special election for the House seat. Even before news of Gillibrand’s appointment broke, Republicans in the district were already jockeying for position in the Congressional race.

Stay tuned to RollCall.com on Friday for more updates.