sentences:  Later that day, Franken filed suit in federal court to force the state to issue a certificate, claiming that federal law relating to Senate elections superseded state law.The next day his campaign asked the Minnesota Supreme Court to require Pawlenty and Ritchie to issue the certificate, and the court held a hearing on the suit on February 5.Texas Senator John Cornyn said that GOP senators were prepared to filibuster the seating of the canvassing board's declared winner until a signed election certificate was available, as provided under Minnesota law.