JACKSONVILLE, Fla. – Campaigning in coveted Florida, President Barack Obama warned Thursday that Republican challenger Mitt Romney would be "squeezing more money out of seniors" by turning Medicare into a voucher program. Romney, firing away near his Boston home base, accused Obama of putting his needs above those of the nation.

The daily war of words came as polling shows the presidential contest continues to be close nationally, with both men pouring most money and attention in into the collection of less than 10 states expected to decide the election. First lady Michelle Obama launched a new effort to rally supporters behind her husband, trying to light a fire by saying the whole race could "come down to just a few votes per precinct in key states."

The president opened two days of campaigning in Florida in search of military veterans, seniors and unaligned voters in the state's crucial midsection. Florida is the largest and most coveted of the nation's Election Day toss-up states, a place where Romney could severely damage Obama's chances of winning re-election.