Millions of Americans are not only upside down on their mortgage; they also appear to be shunning that monthly payment in favor of meeting their everyday expenses, CNNMoney.com reported.

In California, for example, more than 10 percent of consumers with credit cards were choosing to pay those bills rather than their mortgages as of last fall, according to a recent study published by the credit reporting agency TransUnion.

Borrowers across the country have also been just as eager to pay down their home equity line of credit rather than their primary mortgage, based on recent figures from the Federal Deposit Insurance Corp., if for no other reason than so they can continue using their house like an ATM.

History has shown that when cash-strapped consumers are trying to make ends meet, the mortgage is often the first thing people stop paying, said Scott Hoyt, senior director of consumer economics at Moody’s Economy.com.

When the U.S. housing market bubble burst, it had that exact effect, shaking up consumers’ so-called “payment hierarchy.”

In good economic times, consumers usually make payments on their mortgages first, their car loans second and their credit cards and everything else after that.

The TransUnion study revealed that the number of consumers who were delinquent on their mortgage but current on their credit card stood at 6.6 percent in the second half of 2009, up from 4.3 percent at the start of 2008.

Banks have also tried their own programs aimed at getting consumers back on track. Some have attempted modifications on borrowers’ primary mortgage and home equity loans.

The nation’s four largest banks – Citigroup Inc., Wells Fargo & Co., JPMorgan Chase & Co. and Bank of America Corp. – recently agreed to participate in the Obama administration’s Second Lien Modification Program, which aims to stem the rising tide of foreclosures by having banks modify a borrower’s second mortgage.