Redundant, policy-based IPsec VPNs

Is there any way to make redundant IPsec VPNs by using policy-based VPNs?

The situation is that customer remote firewall have two links to the Internet and when the main link goes down, there is no commutation of traffic to the now active, backup link, needing to move it's respective policy before the downed policy to keep the traffic going between the locations.

Or just say, a route-based IPsec VPN would be enough?

Thanks!

Vitor