DENVER (CBS4)– Senator Cory Gardner is among some Republicans expressing concern about the new health care plan to replace the Affordable Care Act or Obamacare.

Republicans released their version on Monday. Americans that earn an income of less than $75,000 a year or families making $150,000 would get a tax credit to offset health care costs.

The credits begin to taper off for families earning more than that in one year.

Sen. Cory Gardner (credit: CBS)

The plan would also freeze enrollment in Medicaid and put a cap on Medicaid grants to states.

Gardner is among some Republicans who believe the plan does not adequately protect those covered through the expansion of Medicaid.

Gardner and three other Republicans wrote a letter outlining their concerns.

The letter states in part that they are “concerned that any poorly implemented or poorly timed change in the current funding structure in Medicaid could result in a reduction in access to life-saving health care services.”