Who has the momentum to win in Iowa?

>>> good evening. i'm harry smith , in for brian tonight. five days to go and eyiowans can't blink without seeing or bumping into a republican presidential candidate . the candidates are making final arguments before tuesday's caucus claiming they have the record, the values and the right stuff to win next november. chuck todd and peter alexander are in iowa tonight. we begin with peter in mason city . peter, good evening.

>> reporter: harry, good evening to you. one sign that mitt romney 's campaign is gaining confidence and looking forward to the opportunity to win here in iowa next week is today they announced they will host a party after tuesday night's caucuses and stay overnight to do tv interviews before heading to new hampshire where romney is heavily favored. before a large crowd in this iowa city that inspired the broadway play "the music man".

>> i feel like breaking into " 76 trombones " but i will not do that now.

>> reporter: frontrunner mitt romney focused his closing argument on patriotic values.

>> o beautiful for patriot dream, that sees beyond the years.

>> reporter: while many iowa republicans are still searching --

>> see how they interact with the crowd.

>> reporter: carlin erickson is leading toward romney because he can win though her political heart lies elsewhere.

>> even though i love michele bachmann and would like to see her maybe be vice president or whatever, i just don't think that she has a chance.

>> reporter: while voters are fuelling romney 's campaign at the last minute others like retired school teacher marge schmidt are frustrated by the choices.

>> i think out of all the people in the whole wide world and the republicans can't find fooind one good person to put up.

>> reporter: the latest to emerge from the republican field, rick santorum , who spent more time in iowa than anyone else believes his success here can make up for lack of resources.

>> i will provide the spark. there is plenty of tinder on the ground that will start building in other states.

>> reporter: analysts wonder if santorum has the political organization for the long haul. trying to stop santorum, rick perry , today launching a new radio campaign.

>> which republican running for president voted for the bridge to nowhere earmark?

>> rick santorum ?

>> correct.

>> reporter: meanwhile michele bachmann accuses the ron paul campaign of buying out a chairman who defected to paul tuesday.

>> he told me specifically he was offered money, a great deal of money from the ron paul campaign .

>> reporter: tonight the ron paul campaign denies that it paid anyone to defect from michele bachmann . tonight, the former campaign manager for herman cain who was the frontrunner said mr. cain has no plans to endorse any republican candidate.