(A) Elements of the offense. A person commits the offense of an attempt when, with intent to commit a specific offense, he or she does any act that constitutes a substantial step toward the commission of that offense.
(B) Impossibility. It is not a defense to a charge of attempt that because of a misapprehension of the circumstances it would have been impossible for the accused to commit the offense attempted.
(C) Sentence. A person convicted of attempt may be fined or imprisoned or both, not to exceed the maximum provided for the offense attempted, but, except for an attempt to commit the offense defined in ILCS Ch. 720, Act 5, § 33A-2:
(1) The sentence for attempt to commit first degree murder is the sentence for a Class X felony, except that:
(a) An attempt to commit first degree murder when at least one of the aggravating factors specified in ILCS Ch. 720, Act 5, § 9-1(b)(1), (2) and (12) is present is a Class X felony for which the sentence shall be a term of imprisonment of not less than 20 years and not more than 80 years;
(b) An attempt to commit first degree murder while armed with a firearm is a Class X felony for which 15 years shall be added to the term of imprisonment imposed by the court;
(c) An attempt to commit first degree murder during which the person personally discharged a firearm is a Class X felony for which 20 years shall be added to the term of imprisonment imposed by the court;
(d) An attempt to commit first degree murder during which the person personally discharged a firearm that proximately caused great bodily harm, permanent disability, permanent disfigurement, or death to another person, is a Class X felony for which 25 years or up to a term of natural life shall be added to the term of imprisonment imposed by the court; and
(e) If the defendant proves by a preponderance of the evidence at sentencing that, at the time of the attempted murder, he or she was acting under a sudden and intense passion resulting from serious provocation by the individual whom the defendant endeavored to kill, or another, and, had the individual the defendant endeavored to kill died, the defendant would have negligently or accidentally caused that death, then the sentence for the attempted murder is the sentence for a Class 1 felony;
(2) The sentence for attempt to commit a Class X felony is the sentence for a Class 2 felony;
(3) The sentence for attempt to commit a Class 1 felony is the sentence for a Class 2 felony;
(4) The sentence for attempt to commit a Class 2 felony is the sentence for a Class 3 felony; and
(5) The sentence for attempt to commit any felony other than those specified in divisions (1), (2), (3), and (4) of this division (C) hereof is the sentence for a Class A misdemeanor.
(ILCS Ch. 720, Act 5, § 8-4) Penalty, see § 130.99