I fly for a major airline and I've known several pilots who had more rotary-wing than fixed wing when they got hired, but they seem to be the exception rather than the rule. However, I agree with the previous postings that your fixed wing time is probably not even close to minimums for most major airlines today.
That being said, have you considered just staying with rotary-wing? Sure, the top pay is probably nowhere close to what you'd make flying for a major airline but there are a lot of helicopter gigs out there that pay a LOT more than regional airline FO, from my understanding. Taking a job like that, while building total time with both rotary and supplementing with fixed wing when you can on your own time (or as a part-time job) would help you to get more competitive without having to put in so much time at the regional airline.
Heck, you might even find you appreciate the schedule a lot more because I would imagine for many of those rotary-wing jobs, you'd be home much more often than flying multi-day trips for an airline. I know a lot of major airline pilots who bid more for lifestyle and Quality-of-Life than for pay alone.
Something to consider.
AIRLINEPILOT CENTRAL