should politicians pay a gift tax on campaign money according to the promises kept and broken?

Yes, make it 50% instead of 30% for accountability and responsibility, and add a little jail time and community service also.

No. Americans overwhelmingly do not hold their politicians accountable for broken campaign promises - whether they are Republican or Democrat. Re-election rates in congress are well over 70% and have been for decades. Polling consistently shows 45% of US votes support Republicans and 45% support Democrats and these levels rarely change no matter what the performance metrics of the government party is -- debt, wars, unemployment, etc. Politifact (and others) obviously have a political agenda. The fact they are only tracking Republican promises is troubling. Further, politicians rarely make direct promises and even if they do vote tallying is often doesn't directly related to promises. It's always an opinion as to whether a vote for or against a bill is breaking your promise. For example, suppose you promised to raise the minimum wage. A 600 page bill comes before you which also raises the minimum wage but also includes a military base expansion, cuts in policing, a farm subsidy extension, closure of two national parks, borrows more from social security, etc.. You vote against the bill. Now some group says that you broke your promise to increase the minimum wage. Vote for it and another group screams that you broke your promise on protecting social security. There is no one-to-one relationship between most votes and promises. Both parties will continue to blame each other and in both cases their supporters will accept this and not see 'their' officials as the problem. Americans just overwhelmingly see all issues in terms of Democrat vs. Republican and vote that way regardless of performance.

Politicians should be legally required to sign a contract requiring they complete at least a rather large percentage of their campaign promises. If they do not, they will suffer the consequences. Be it jail time or large fines or both.

Yeah, we wish.