U.S. Republican presidential contender Mitt Romney has arrived at his party's national convention, where his wife Ann and his supporters are set to make their case to voters why he should replace President Barack Obama as the American leader.

Mr. Romney flew Tuesday to the host city of Tampa, Florida, to witness his wife's primetime television speech to the Republican National Convention. New Jersey Governor Chris Christie closes the night with his keynote address.

On the flight to Florida, Mrs. Romney told reporters she would speak from the heart about her husband of 43 years.

“You will see that my speech is heartfelt. I think a lot of you have been covering me long enough that you know that I have never gone off of a written text, so this is a unique experience for me.”

Party officials are hoping Mrs. Romney's speech will showcase a more personal side of the Republican candidate than the image the Obama campaign has painted of him as a wealthy businessman who has little in connection with everyday Americans and their economic concerns. Meanwhile, Christie is expected to pinpoint what Republicans see as the significant failures of Mr. Obama's White House tenure over the last three-and-a-half years.

Before their speeches, party leaders planned to call the roll of state delegations to the convention for a formal vote nominating Mr. Romney as the party's candidate in the November 6 election.

Tuesday is the first full day of the Republican convention, with most events canceled Monday as Tropical Storm Isaac skirted Florida's western coastline before becoming a hurricane. Convention officials are still watching the storm's path as it heads toward the northern coast of the Gulf of Mexico for a possible landfall late Tuesday or early Wednesday in Louisiana and it could again force changes in the convention schedule.

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.

An opinion poll published Monday in The Washington Post shows President Obama, the Democratic incumbent, and Mr. Romney in a tight contest. 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 in Charlotte, North Carolina.