Right now, I would say yes, with the caveat that it's not your entire collection :D With the end of the season, and some other people dumping their rentals back on the market, it looks like you can get enough cards to get to Gold III power for about 110 DEC a day and delegating a few cards from my main account.

That's not too hard to maintain if I let the ECR go back up, and not grind 100 matches a day :D That's what I'm planning on doing with the account right now anyhow. I may try to push into Diamond again at the end of the next season, but I figure I'll just play an extra 10 or so matches a day to get extra daily rewards (hopefully only 10 or so!)

Thanks for replying!