WASHINGTON (CNN) -- Officials with the McCain campaign and the Republican National convention are considering changing the event's agenda as Hurricane Gustav bears down on the Gulf Coast.

The Republican National Convention is set to kick off Monday in Minneapolis-St.Paul, Minnesota.

Sen. John McCain's campaign manager, Rick Davis, plans to meet with officials in charge of the party's convention planning in Minneapolis-St. Paul on Sunday to review the latest news on Hurricane Gustav and what their options might be and then consult with the presumptive presidential nominee to determine what changes may need to be made.

"I wouldn't call it a nightmare, but it is a very perplexing challenge," said a GOP official planning the event.

A senior McCain source said Saturday that officials are considering turning the convention into a service event, a massive telethon to raise money for the Red Cross and other agencies to help with the hurricane.

"He wants to do something service-oriented if and when the storm hits and it's as bad as its expected to be now," the McCain source said.

They are also hoping to get McCain himself to a storm-affected area as soon as possible.

McCain had suggested to a Fox News interviewer that the convention could be suspended if it seemed that a festive gathering was inappropriate in light of the destruction the storm may bring. Watch as the Gulf Coast prepares for Gustav »

President Bush, who is scheduled to address the convention Monday night, is making contingency plans in case the storm keeps him in Washington.

White House spokeswoman Dana Perino said there are "no schedule changes yet, but we're making contingency plans" because of the hurricane. She said it is a "serious and scary situation," so the White House is "closely monitoring" the storm.

A Republican official involved in convention planning said that various options are being explored, including having the president speak to Republican delegates via satellite and updating them on the storm rather than traveling to Minnesota.

Perino said she expects to have more details by Sunday morning.

Republican Govs. Bobby Jindal of Louisiana, Charlie Crist of Florida, Haley Barbour of Mississippi and Rick Perry of Texas -- whose states that lie in the path of Gustav, named a Category 4 hurricane Saturday afternoon -- will skip the GOP convention because of the storm.

The storm has forced last-minute changes in the convention's announced schedule: If the convention -- originally scheduled to start Monday -- commences by Tuesday, former Massachusetts Gov. Mitt Romney's speech will probably move to that night from Wednesday.

Other changes were being contemplated Saturday afternoon.

The hardest decisions, like whether to cancel a day or two of the four-day gathering or to or condense days, will be made at the last second, GOP officials said. But the logistics of those decisions are being discussed.

There are two scenarios under consideration for Bush's speech, slated for Monday night. If the president is on hand to speak, his wife, Laura, will give a short speech. If he is not, the first lady will give a longer speech, and the president will speak via satellite.

That decision will probably not be made until Sunday evening or Monday.

Officials won't discuss in detail how McCain's plans might change. They won't talk about McCain in any detail, but he is likely to go Monday or Tuesday to an aid station in an area hit by the hurricane, if it continues on as expected.

Earlier Saturday, President Bush declared a state of emergency in Mississippi, following similar declarations in Louisiana and Texas.

The president ordered federal aid to supplement state and local efforts in the areas in the forecast path of Hurricane Gustav.

Bush checked in with the four governors whose states are in Gustav's potential route.

The president pledged the full support of the federal government to those states, White House spokesman Scott Stanzel said.

Bush and his administration were heavily criticized in 2005 for not moving fast enough to send federal help to the Gulf Coast when Hurricane Katrina hit.

CNN's Dana Bash, Ed Hornick, John King and Rebecca Sinderbrand contributed to this report.

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