U.S. Republicans hold the first full day of their national convention Tuesday, pushing to highlight their policies and presidential candidate Mitt Romney while a tropical storm threatens to overshadow the event's celebratory tone.

Romney is set to arrive in the host city of Tampa, Florida Tuesday, but aides have not said if he will be in attendance during his wife Ann's primetime speech. New Jersey Governor Chris Christie closes the night with his keynote address.

The Republican Party formally opened its nominating convention Monday but postponed most of the proceedings as Tropical Storm Isaac skirted the Florida coastline. Forecasters say the storm could strengthen into a hurricane before striking Louisiana late Tuesday or early Wednesday.

Romney aide Russ Schriefer told reporters in Tampa the campaign is concerned about the people in the path of the storm and may revise the convention's schedule again.

The Republican governor of Louisiana, Bobby Jindal, canceled his planned convention speech, saying he was staying home to deal with the prospect of Isaac hitting his state.

A Washington Post opinion poll published Monday shows President Barack Obama, the Democratic incumbent, and Mr. Romney in a tight race for the November presidential election. It says Mr. Romney has the support of 47 percent of likely voters compared to 46 percent for Mr. Obama — little changed from early July's figures.

Mr. Obama is spending Tuesday and Wednesday campaigning in college towns in Iowa, Colorado and Virginia. The Democrats hold their convention next week.