Yes you can. It is fairly simple to do. Create a multiline button and use that. The "trick" is to set the titleLabel numberOfLines property so that it likes multilines.
UIButton* button = [UIButton buttonWithType:UIButtonTypeCustom];
button.titleLabel.numberOfLines = 0;
[button setTitle:NSLocalizedString(@"Now
Playing", nil) forState:UIControlStateNormal];
[button sizeToFit];
self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:button];
When you specify a button type of custom it expects you to configure everything... selected state, etc. which is not shown here to keep the answer focused to the problem at hand.
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