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President Obama's speech to the Democratic National Convention has been moved indoors. Instead of addressing convention delegates from the Bank of America Stadium, where organizers had hoped to seat 65,000, the president will speak at the much-smaller Time Warner Cable Arena, which can fit 20,000 and where the rest of the convention is also taking place.

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Convention organizers cited a weather forecast that includes a 30 percent chance of isolated thunderstorms as the reason for the last-minute switch.

"We have been monitoring weather forecasts closely and several reports predict thunderstorms in the area, therefore we have decided to move Thursday's proceedings to Time Warner Cable Arena to ensure the safety and security of our delegates and convention guests," Steve Kerrigan, CEO of the convention's organizing committee, said in a statement. "The energy and enthusiasm for our convention in Charlotte has been overwhelming and we share the disappointment of over 65,000 people who signed up for community credentials to be there with the president in person."

President Obama will host a conference call for the many thousands who won't fit into the Time Warner arena.

The switch indoors was caused by the weather, but it's the latest paring back of the Democrats' convention, which was originally supposed to last four days, but was cut to three.

Obama's 2008 convention speech was made to a packed crowd at Denver's INVESCO field, which held 84,000 people for the event. Republicans were quick to suggest that the weather was an excuse for lack of enthusiasm.

Andrea Saul, Mitt Romney's campaign spokeswoman tweeted, "What happened 2 rain or shine?"

Another Romney spokesman, Ryan Williams, tweeted a weather report from a Charlotte meteorologist. "@wxbrad: Severe threat is almost 0 Thur night & chance of rain 20%"

And RNC spokeswoman Kirsten Kukowski said, "Democrats continue to downgrade convention events due to lack of enthusiasm - this time they are moving out of Bank of America/Panther stadium. Problems filling the seats?"

Here's the forecast from Accuweather.com, which has a less than 50 percent chance of thunderstorms, but suggests if they do occur it would be late in the evening when President Obama would speak.