The U.S. debt compromise deadline is days away with the prospect of a national downgrade looming in lieu of a solution. In such an instance, it is likely that bonds issued by Fannie Mae and Freddie Mac will experience an implied downgrade as well, considering the implied government backing. Indeed, in a commentary in The Washington Post, Neel Kashkari, managing director of the investment management firm PIMCO, suggested a U.S. downgrade has the potential to be as bad or perhaps worse than the Lehman Bros.' shock. "The more strongly held a belief, and the larger the asset class it supports, the greater the potential damage to the economy when the belief is turned upside down," he writes. "We may not be certain what will happen if U.S. credit is downgraded, but there is no upside to finding out." However, analysts at Barclays Capital are not as worried when it comes to Fannie Mae and Freddie Mac. They say among the largest investors of these bonds, there is little chance of a widescale withdrawal from the market. Banks have been a major source of demand for mortgage-backed securities this year, alongside real estate investment trusts, adding in excess of $100 billion in the past three quarters. They admit that an investor concern is that a downgrade could sap bank demand by potentially raising the level of regulatory capital that must be held against the asset. "But we do not think this will be the case," they say. "We see the likelihood of regulatory capital increases based on a rating downgrade as extremely low," the Barclays Capital analysts write. "As such, in the event of a downgrade, there should not be much change in bank demand for this sector." See the investor breakdown for Fannie, Freddie below. Write to Jacob Gaffney. Follow him on Twitter @jacobgaffney.