Marco Rubio's return to Iowa dampened by the weather

Republican presidential candidate, Sen. Marco Rubio, R-Fla., checks the sky as he tours the grounds during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

Republican presidential candidate, Sen. Marco Rubio, R-Fla., poses for a photo with fairgoers during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

Republican presidential candidate, Sen. Marco Rubio, R-Fla., greets fairgoers during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

Republican presidential candidate, Sen. Marco Rubio, R-Fla., walks with Sen. Chuck Grassley, R-Iowa, rear, during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

Republican presidential candidate, Sen. Marco Rubio, R-Fla., casts a vote for himself in a corn poll sponsored by a local television station during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

Republican presidential candidate, Sen. Marco Rubio, R-Fla., works the grill in the Iowa Pork Producers Tent with Rep. David Young, R-Iowa, right, during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

Republican presidential candidate, Sen. Marco Rubio, R-Fla., visits the Republican Party of Iowa booth during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

Republican presidential candidate, Sen. Marco Rubio, R-Fla., speaks during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

A supporter listens as Republican presidential candidate, Sen. Marco Rubio, R-Fla., speaks during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

Republican presidential candidate, Sen. Marco Rubio, R-Fla., speaks to the media during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)

Republican presidential candidate, Sen. Marco Rubio, R-Fla., speaks to a reporter as he tours the cattle barn during a visit to the Iowa State Fair, Tuesday, Aug. 18, 2015, in Des Moines, Iowa. (AP Photo/Charlie Neibergall)