Good news is that low GPAs can be raised. The bad news is depending upon how "low" you are it could mean taking the equal of two, three, or even four years of college/university courses to do so; this is particularly true when taking a "C" GPA up to the "B+" or better "A" average most nursing programs
are seeking these days.
It has been years (thank God! *LOL*) since one has had to do the sums, but IIRC for every "C" grade you need about two "A" grades to negate the damage to your average. Case in point, even if you were to take every single pre-nursing pre-req or whatever classes and obtain a 4.0 GPA, your overall average between the two would only be around 3.2 (if one has got the sums correct). While such as average is a solid "B" and in days past would have been no problem for admissions, today in most areas that is the floor with a good percentage of applicants around 3.5 with a decent number at 4.0.
Your best bet would be to follow the advice above and seek out programs that look at a "total" picture of an applicant. Such programs may be easier than those whom merely assign rankings based upon GPAs and often test (HESI, NLN) scores.
Standardised pre-nursing admission exams such as the NLN or HESI can give you room to shine for some but not all programs. If you can knock that ball out of the park with an super great score, coupled with all A's or at least a 3.0 to 3.5 in pre-nursing classes (A&P, Micro, Chem, etc...) you can point to those achievements to show you aren't the same person who graduated university. Again you may have to seek out a NP that gives weight to personal interviews, essays, and so forth over straight rankings but it could be worth a shot.
Most main line nursing programs are concerned with admitting applicants deemed academically prepared and suited for the difficult road ahead. There are more than a few studies that have proven a link between academic success (measured by GPAs at or over 3.0) in a nursing program and passing the NCLEX on the first attempt. Sadly that last bit is what often concerns many nursing programs.
However make no mistake, nursing school never was a cake walk and today even less. Many persons have the desire to become a nurse but sadly academically it simply is beyond them. Look back over your prior college experience and sort yourself out. Were you "lazy" and or just didn't apply yourself? What will be different this time around? Can you handle the required science and math classes? How are your basic (up to about freshman year high school) math skills?
Getting into a nursing program is half the battle, staying put is often the problem for some. Keep in mind many hospitals are now asking to see new grad's transcripts and seek out those with at least a 3.0 or above if not overall GPA but certainly science and nursing classes.